/**

* @license
* Lodash <https://lodash.com/>
* Copyright OpenJS Foundation and other contributors <https://openjsf.org/>
* Released under MIT license <https://lodash.com/license>
* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
* Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
*/

;(function() {

/** Used as a safe reference for `undefined` in pre-ES5 environments. */
var undefined;

/** Used as the semantic version number. */
var VERSION = '4.17.15';

/** Used as the size to enable large array optimizations. */
var LARGE_ARRAY_SIZE = 200;

/** Error message constants. */
var CORE_ERROR_TEXT = 'Unsupported core-js use. Try https://npms.io/search?q=ponyfill.',
    FUNC_ERROR_TEXT = 'Expected a function';

/** Used to stand-in for `undefined` hash values. */
var HASH_UNDEFINED = '__lodash_hash_undefined__';

/** Used as the maximum memoize cache size. */
var MAX_MEMOIZE_SIZE = 500;

/** Used as the internal argument placeholder. */
var PLACEHOLDER = '__lodash_placeholder__';

/** Used to compose bitmasks for cloning. */
var CLONE_DEEP_FLAG = 1,
    CLONE_FLAT_FLAG = 2,
    CLONE_SYMBOLS_FLAG = 4;

/** Used to compose bitmasks for value comparisons. */
var COMPARE_PARTIAL_FLAG = 1,
    COMPARE_UNORDERED_FLAG = 2;

/** Used to compose bitmasks for function metadata. */
var WRAP_BIND_FLAG = 1,
    WRAP_BIND_KEY_FLAG = 2,
    WRAP_CURRY_BOUND_FLAG = 4,
    WRAP_CURRY_FLAG = 8,
    WRAP_CURRY_RIGHT_FLAG = 16,
    WRAP_PARTIAL_FLAG = 32,
    WRAP_PARTIAL_RIGHT_FLAG = 64,
    WRAP_ARY_FLAG = 128,
    WRAP_REARG_FLAG = 256,
    WRAP_FLIP_FLAG = 512;

/** Used as default options for `_.truncate`. */
var DEFAULT_TRUNC_LENGTH = 30,
    DEFAULT_TRUNC_OMISSION = '...';

/** Used to detect hot functions by number of calls within a span of milliseconds. */
var HOT_COUNT = 800,
    HOT_SPAN = 16;

/** Used to indicate the type of lazy iteratees. */
var LAZY_FILTER_FLAG = 1,
    LAZY_MAP_FLAG = 2,
    LAZY_WHILE_FLAG = 3;

/** Used as references for various `Number` constants. */
var INFINITY = 1 / 0,
    MAX_SAFE_INTEGER = 9007199254740991,
    MAX_INTEGER = 1.7976931348623157e+308,
    NAN = 0 / 0;

/** Used as references for the maximum length and index of an array. */
var MAX_ARRAY_LENGTH = 4294967295,
    MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1,
    HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;

/** Used to associate wrap methods with their bit flags. */
var wrapFlags = [
  ['ary', WRAP_ARY_FLAG],
  ['bind', WRAP_BIND_FLAG],
  ['bindKey', WRAP_BIND_KEY_FLAG],
  ['curry', WRAP_CURRY_FLAG],
  ['curryRight', WRAP_CURRY_RIGHT_FLAG],
  ['flip', WRAP_FLIP_FLAG],
  ['partial', WRAP_PARTIAL_FLAG],
  ['partialRight', WRAP_PARTIAL_RIGHT_FLAG],
  ['rearg', WRAP_REARG_FLAG]
];

/** `Object#toString` result references. */
var argsTag = '[object Arguments]',
    arrayTag = '[object Array]',
    asyncTag = '[object AsyncFunction]',
    boolTag = '[object Boolean]',
    dateTag = '[object Date]',
    domExcTag = '[object DOMException]',
    errorTag = '[object Error]',
    funcTag = '[object Function]',
    genTag = '[object GeneratorFunction]',
    mapTag = '[object Map]',
    numberTag = '[object Number]',
    nullTag = '[object Null]',
    objectTag = '[object Object]',
    promiseTag = '[object Promise]',
    proxyTag = '[object Proxy]',
    regexpTag = '[object RegExp]',
    setTag = '[object Set]',
    stringTag = '[object String]',
    symbolTag = '[object Symbol]',
    undefinedTag = '[object Undefined]',
    weakMapTag = '[object WeakMap]',
    weakSetTag = '[object WeakSet]';

var arrayBufferTag = '[object ArrayBuffer]',
    dataViewTag = '[object DataView]',
    float32Tag = '[object Float32Array]',
    float64Tag = '[object Float64Array]',
    int8Tag = '[object Int8Array]',
    int16Tag = '[object Int16Array]',
    int32Tag = '[object Int32Array]',
    uint8Tag = '[object Uint8Array]',
    uint8ClampedTag = '[object Uint8ClampedArray]',
    uint16Tag = '[object Uint16Array]',
    uint32Tag = '[object Uint32Array]';

/** Used to match empty string literals in compiled template source. */
var reEmptyStringLeading = /\b__p \+= '';/g,
    reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
    reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;

/** Used to match HTML entities and HTML characters. */
var reEscapedHtml = /&(?:amp|lt|gt|quot|#39);/g,
    reUnescapedHtml = /[&<>"']/g,
    reHasEscapedHtml = RegExp(reEscapedHtml.source),
    reHasUnescapedHtml = RegExp(reUnescapedHtml.source);

/** Used to match template delimiters. */
var reEscape = /<%-([\s\S]+?)%>/g,
    reEvaluate = /<%([\s\S]+?)%>/g,
    reInterpolate = /<%=([\s\S]+?)%>/g;

/** Used to match property names within property paths. */
var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/,
    reIsPlainProp = /^\w*$/,
    rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]|(?=(?:\.|\[\])(?:\.|\[\]|$))/g;

/**
 * Used to match `RegExp`
 * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns).
 */
var reRegExpChar = /[\\^$.*+?()[\]{}|]/g,
    reHasRegExpChar = RegExp(reRegExpChar.source);

/** Used to match leading and trailing whitespace. */
var reTrim = /^\s+|\s+$/g,
    reTrimStart = /^\s+/,
    reTrimEnd = /\s+$/;

/** Used to match wrap detail comments. */
var reWrapComment = /\{(?:\n\/\* \[wrapped with .+\] \*\/)?\n?/,
    reWrapDetails = /\{\n\/\* \[wrapped with (.+)\] \*/,
    reSplitDetails = /,? & /;

/** Used to match words composed of alphanumeric characters. */
var reAsciiWord = /[^\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\x7f]+/g;

/** Used to match backslashes in property paths. */
var reEscapeChar = /\\(\\)?/g;

/**
 * Used to match
 * [ES template delimiters](http://ecma-international.org/ecma-262/7.0/#sec-template-literal-lexical-components).
 */
var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;

/** Used to match `RegExp` flags from their coerced string values. */
var reFlags = /\w*$/;

/** Used to detect bad signed hexadecimal string values. */
var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;

/** Used to detect binary string values. */
var reIsBinary = /^0b[01]+$/i;

/** Used to detect host constructors (Safari). */
var reIsHostCtor = /^\[object .+?Constructor\]$/;

/** Used to detect octal string values. */
var reIsOctal = /^0o[0-7]+$/i;

/** Used to detect unsigned integer values. */
var reIsUint = /^(?:0|[1-9]\d*)$/;

/** Used to match Latin Unicode letters (excluding mathematical operators). */
var reLatin = /[\xc0-\xd6\xd8-\xf6\xf8-\xff\u0100-\u017f]/g;

/** Used to ensure capturing order of template delimiters. */
var reNoMatch = /($^)/;

/** Used to match unescaped characters in compiled string literals. */
var reUnescapedString = /['\n\r\u2028\u2029\\]/g;

/** Used to compose unicode character classes. */
var rsAstralRange = '\\ud800-\\udfff',
    rsComboMarksRange = '\\u0300-\\u036f',
    reComboHalfMarksRange = '\\ufe20-\\ufe2f',
    rsComboSymbolsRange = '\\u20d0-\\u20ff',
    rsComboRange = rsComboMarksRange + reComboHalfMarksRange + rsComboSymbolsRange,
    rsDingbatRange = '\\u2700-\\u27bf',
    rsLowerRange = 'a-z\\xdf-\\xf6\\xf8-\\xff',
    rsMathOpRange = '\\xac\\xb1\\xd7\\xf7',
    rsNonCharRange = '\\x00-\\x2f\\x3a-\\x40\\x5b-\\x60\\x7b-\\xbf',
    rsPunctuationRange = '\\u2000-\\u206f',
    rsSpaceRange = ' \\t\\x0b\\f\\xa0\\ufeff\\n\\r\\u2028\\u2029\\u1680\\u180e\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000',
    rsUpperRange = 'A-Z\\xc0-\\xd6\\xd8-\\xde',
    rsVarRange = '\\ufe0e\\ufe0f',
    rsBreakRange = rsMathOpRange + rsNonCharRange + rsPunctuationRange + rsSpaceRange;

/** Used to compose unicode capture groups. */
var rsApos = "['\u2019]",
    rsAstral = '[' + rsAstralRange + ']',
    rsBreak = '[' + rsBreakRange + ']',
    rsCombo = '[' + rsComboRange + ']',
    rsDigits = '\\d+',
    rsDingbat = '[' + rsDingbatRange + ']',
    rsLower = '[' + rsLowerRange + ']',
    rsMisc = '[^' + rsAstralRange + rsBreakRange + rsDigits + rsDingbatRange + rsLowerRange + rsUpperRange + ']',
    rsFitz = '\\ud83c[\\udffb-\\udfff]',
    rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')',
    rsNonAstral = '[^' + rsAstralRange + ']',
    rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}',
    rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]',
    rsUpper = '[' + rsUpperRange + ']',
    rsZWJ = '\\u200d';

/** Used to compose unicode regexes. */
var rsMiscLower = '(?:' + rsLower + '|' + rsMisc + ')',
    rsMiscUpper = '(?:' + rsUpper + '|' + rsMisc + ')',
    rsOptContrLower = '(?:' + rsApos + '(?:d|ll|m|re|s|t|ve))?',
    rsOptContrUpper = '(?:' + rsApos + '(?:D|LL|M|RE|S|T|VE))?',
    reOptMod = rsModifier + '?',
    rsOptVar = '[' + rsVarRange + ']?',
    rsOptJoin = '(?:' + rsZWJ + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*',
    rsOrdLower = '\\d*(?:1st|2nd|3rd|(?![123])\\dth)(?=\\b|[A-Z_])',
    rsOrdUpper = '\\d*(?:1ST|2ND|3RD|(?![123])\\dTH)(?=\\b|[a-z_])',
    rsSeq = rsOptVar + reOptMod + rsOptJoin,
    rsEmoji = '(?:' + [rsDingbat, rsRegional, rsSurrPair].join('|') + ')' + rsSeq,
    rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')';

/** Used to match apostrophes. */
var reApos = RegExp(rsApos, 'g');

/**
 * Used to match [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks) and
 * [combining diacritical marks for symbols](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks_for_Symbols).
 */
var reComboMark = RegExp(rsCombo, 'g');

/** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */
var reUnicode = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g');

/** Used to match complex or compound words. */
var reUnicodeWord = RegExp([
  rsUpper + '?' + rsLower + '+' + rsOptContrLower + '(?=' + [rsBreak, rsUpper, '$'].join('|') + ')',
  rsMiscUpper + '+' + rsOptContrUpper + '(?=' + [rsBreak, rsUpper + rsMiscLower, '$'].join('|') + ')',
  rsUpper + '?' + rsMiscLower + '+' + rsOptContrLower,
  rsUpper + '+' + rsOptContrUpper,
  rsOrdUpper,
  rsOrdLower,
  rsDigits,
  rsEmoji
].join('|'), 'g');

/** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */
var reHasUnicode = RegExp('[' + rsZWJ + rsAstralRange  + rsComboRange + rsVarRange + ']');

/** Used to detect strings that need a more robust regexp to match words. */
var reHasUnicodeWord = /[a-z][A-Z]|[A-Z]{2}[a-z]|[0-9][a-zA-Z]|[a-zA-Z][0-9]|[^a-zA-Z0-9 ]/;

/** Used to assign default `context` object properties. */
var contextProps = [
  'Array', 'Buffer', 'DataView', 'Date', 'Error', 'Float32Array', 'Float64Array',
  'Function', 'Int8Array', 'Int16Array', 'Int32Array', 'Map', 'Math', 'Object',
  'Promise', 'RegExp', 'Set', 'String', 'Symbol', 'TypeError', 'Uint8Array',
  'Uint8ClampedArray', 'Uint16Array', 'Uint32Array', 'WeakMap',
  '_', 'clearTimeout', 'isFinite', 'parseInt', 'setTimeout'
];

/** Used to make template sourceURLs easier to identify. */
var templateCounter = -1;

/** Used to identify `toStringTag` values of typed arrays. */
var typedArrayTags = {};
typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
typedArrayTags[uint32Tag] = true;
typedArrayTags[argsTag] = typedArrayTags[arrayTag] =
typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
typedArrayTags[dataViewTag] = typedArrayTags[dateTag] =
typedArrayTags[errorTag] = typedArrayTags[funcTag] =
typedArrayTags[mapTag] = typedArrayTags[numberTag] =
typedArrayTags[objectTag] = typedArrayTags[regexpTag] =
typedArrayTags[setTag] = typedArrayTags[stringTag] =
typedArrayTags[weakMapTag] = false;

/** Used to identify `toStringTag` values supported by `_.clone`. */
var cloneableTags = {};
cloneableTags[argsTag] = cloneableTags[arrayTag] =
cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] =
cloneableTags[boolTag] = cloneableTags[dateTag] =
cloneableTags[float32Tag] = cloneableTags[float64Tag] =
cloneableTags[int8Tag] = cloneableTags[int16Tag] =
cloneableTags[int32Tag] = cloneableTags[mapTag] =
cloneableTags[numberTag] = cloneableTags[objectTag] =
cloneableTags[regexpTag] = cloneableTags[setTag] =
cloneableTags[stringTag] = cloneableTags[symbolTag] =
cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] =
cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true;
cloneableTags[errorTag] = cloneableTags[funcTag] =
cloneableTags[weakMapTag] = false;

/** Used to map Latin Unicode letters to basic Latin letters. */
var deburredLetters = {
  // Latin-1 Supplement block.
  '\xc0': 'A',  '\xc1': 'A', '\xc2': 'A', '\xc3': 'A', '\xc4': 'A', '\xc5': 'A',
  '\xe0': 'a',  '\xe1': 'a', '\xe2': 'a', '\xe3': 'a', '\xe4': 'a', '\xe5': 'a',
  '\xc7': 'C',  '\xe7': 'c',
  '\xd0': 'D',  '\xf0': 'd',
  '\xc8': 'E',  '\xc9': 'E', '\xca': 'E', '\xcb': 'E',
  '\xe8': 'e',  '\xe9': 'e', '\xea': 'e', '\xeb': 'e',
  '\xcc': 'I',  '\xcd': 'I', '\xce': 'I', '\xcf': 'I',
  '\xec': 'i',  '\xed': 'i', '\xee': 'i', '\xef': 'i',
  '\xd1': 'N',  '\xf1': 'n',
  '\xd2': 'O',  '\xd3': 'O', '\xd4': 'O', '\xd5': 'O', '\xd6': 'O', '\xd8': 'O',
  '\xf2': 'o',  '\xf3': 'o', '\xf4': 'o', '\xf5': 'o', '\xf6': 'o', '\xf8': 'o',
  '\xd9': 'U',  '\xda': 'U', '\xdb': 'U', '\xdc': 'U',
  '\xf9': 'u',  '\xfa': 'u', '\xfb': 'u', '\xfc': 'u',
  '\xdd': 'Y',  '\xfd': 'y', '\xff': 'y',
  '\xc6': 'Ae', '\xe6': 'ae',
  '\xde': 'Th', '\xfe': 'th',
  '\xdf': 'ss',
  // Latin Extended-A block.
  '\u0100': 'A',  '\u0102': 'A', '\u0104': 'A',
  '\u0101': 'a',  '\u0103': 'a', '\u0105': 'a',
  '\u0106': 'C',  '\u0108': 'C', '\u010a': 'C', '\u010c': 'C',
  '\u0107': 'c',  '\u0109': 'c', '\u010b': 'c', '\u010d': 'c',
  '\u010e': 'D',  '\u0110': 'D', '\u010f': 'd', '\u0111': 'd',
  '\u0112': 'E',  '\u0114': 'E', '\u0116': 'E', '\u0118': 'E', '\u011a': 'E',
  '\u0113': 'e',  '\u0115': 'e', '\u0117': 'e', '\u0119': 'e', '\u011b': 'e',
  '\u011c': 'G',  '\u011e': 'G', '\u0120': 'G', '\u0122': 'G',
  '\u011d': 'g',  '\u011f': 'g', '\u0121': 'g', '\u0123': 'g',
  '\u0124': 'H',  '\u0126': 'H', '\u0125': 'h', '\u0127': 'h',
  '\u0128': 'I',  '\u012a': 'I', '\u012c': 'I', '\u012e': 'I', '\u0130': 'I',
  '\u0129': 'i',  '\u012b': 'i', '\u012d': 'i', '\u012f': 'i', '\u0131': 'i',
  '\u0134': 'J',  '\u0135': 'j',
  '\u0136': 'K',  '\u0137': 'k', '\u0138': 'k',
  '\u0139': 'L',  '\u013b': 'L', '\u013d': 'L', '\u013f': 'L', '\u0141': 'L',
  '\u013a': 'l',  '\u013c': 'l', '\u013e': 'l', '\u0140': 'l', '\u0142': 'l',
  '\u0143': 'N',  '\u0145': 'N', '\u0147': 'N', '\u014a': 'N',
  '\u0144': 'n',  '\u0146': 'n', '\u0148': 'n', '\u014b': 'n',
  '\u014c': 'O',  '\u014e': 'O', '\u0150': 'O',
  '\u014d': 'o',  '\u014f': 'o', '\u0151': 'o',
  '\u0154': 'R',  '\u0156': 'R', '\u0158': 'R',
  '\u0155': 'r',  '\u0157': 'r', '\u0159': 'r',
  '\u015a': 'S',  '\u015c': 'S', '\u015e': 'S', '\u0160': 'S',
  '\u015b': 's',  '\u015d': 's', '\u015f': 's', '\u0161': 's',
  '\u0162': 'T',  '\u0164': 'T', '\u0166': 'T',
  '\u0163': 't',  '\u0165': 't', '\u0167': 't',
  '\u0168': 'U',  '\u016a': 'U', '\u016c': 'U', '\u016e': 'U', '\u0170': 'U', '\u0172': 'U',
  '\u0169': 'u',  '\u016b': 'u', '\u016d': 'u', '\u016f': 'u', '\u0171': 'u', '\u0173': 'u',
  '\u0174': 'W',  '\u0175': 'w',
  '\u0176': 'Y',  '\u0177': 'y', '\u0178': 'Y',
  '\u0179': 'Z',  '\u017b': 'Z', '\u017d': 'Z',
  '\u017a': 'z',  '\u017c': 'z', '\u017e': 'z',
  '\u0132': 'IJ', '\u0133': 'ij',
  '\u0152': 'Oe', '\u0153': 'oe',
  '\u0149': "'n", '\u017f': 's'
};

/** Used to map characters to HTML entities. */
var htmlEscapes = {
  '&': '&amp;',
  '<': '&lt;',
  '>': '&gt;',
  '"': '&quot;',
  "'": '&#39;'
};

/** Used to map HTML entities to characters. */
var htmlUnescapes = {
  '&amp;': '&',
  '&lt;': '<',
  '&gt;': '>',
  '&quot;': '"',
  '&#39;': "'"
};

/** Used to escape characters for inclusion in compiled string literals. */
var stringEscapes = {
  '\\': '\\',
  "'": "'",
  '\n': 'n',
  '\r': 'r',
  '\u2028': 'u2028',
  '\u2029': 'u2029'
};

/** Built-in method references without a dependency on `root`. */
var freeParseFloat = parseFloat,
    freeParseInt = parseInt;

/** Detect free variable `global` from Node.js. */
var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;

/** Detect free variable `self`. */
var freeSelf = typeof self == 'object' && self && self.Object === Object && self;

/** Used as a reference to the global object. */
var root = freeGlobal || freeSelf || Function('return this')();

/** Detect free variable `exports`. */
var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports;

/** Detect free variable `module`. */
var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module;

/** Detect the popular CommonJS extension `module.exports`. */
var moduleExports = freeModule && freeModule.exports === freeExports;

/** Detect free variable `process` from Node.js. */
var freeProcess = moduleExports && freeGlobal.process;

/** Used to access faster Node.js helpers. */
var nodeUtil = (function() {
  try {
    // Use `util.types` for Node.js 10+.
    var types = freeModule && freeModule.require && freeModule.require('util').types;

    if (types) {
      return types;
    }

    // Legacy `process.binding('util')` for Node.js < 10.
    return freeProcess && freeProcess.binding && freeProcess.binding('util');
  } catch (e) {}
}());

/* Node.js helper references. */
var nodeIsArrayBuffer = nodeUtil && nodeUtil.isArrayBuffer,
    nodeIsDate = nodeUtil && nodeUtil.isDate,
    nodeIsMap = nodeUtil && nodeUtil.isMap,
    nodeIsRegExp = nodeUtil && nodeUtil.isRegExp,
    nodeIsSet = nodeUtil && nodeUtil.isSet,
    nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;

/*--------------------------------------------------------------------------*/

/**
 * A faster alternative to `Function#apply`, this function invokes `func`
 * with the `this` binding of `thisArg` and the arguments of `args`.
 *
 * @private
 * @param {Function} func The function to invoke.
 * @param {*} thisArg The `this` binding of `func`.
 * @param {Array} args The arguments to invoke `func` with.
 * @returns {*} Returns the result of `func`.
 */
function apply(func, thisArg, args) {
  switch (args.length) {
    case 0: return func.call(thisArg);
    case 1: return func.call(thisArg, args[0]);
    case 2: return func.call(thisArg, args[0], args[1]);
    case 3: return func.call(thisArg, args[0], args[1], args[2]);
  }
  return func.apply(thisArg, args);
}

/**
 * A specialized version of `baseAggregator` for arrays.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} setter The function to set `accumulator` values.
 * @param {Function} iteratee The iteratee to transform keys.
 * @param {Object} accumulator The initial aggregated object.
 * @returns {Function} Returns `accumulator`.
 */
function arrayAggregator(array, setter, iteratee, accumulator) {
  var index = -1,
      length = array == null ? 0 : array.length;

  while (++index < length) {
    var value = array[index];
    setter(accumulator, value, iteratee(value), array);
  }
  return accumulator;
}

/**
 * A specialized version of `_.forEach` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {Array} Returns `array`.
 */
function arrayEach(array, iteratee) {
  var index = -1,
      length = array == null ? 0 : array.length;

  while (++index < length) {
    if (iteratee(array[index], index, array) === false) {
      break;
    }
  }
  return array;
}

/**
 * A specialized version of `_.forEachRight` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {Array} Returns `array`.
 */
function arrayEachRight(array, iteratee) {
  var length = array == null ? 0 : array.length;

  while (length--) {
    if (iteratee(array[length], length, array) === false) {
      break;
    }
  }
  return array;
}

/**
 * A specialized version of `_.every` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} predicate The function invoked per iteration.
 * @returns {boolean} Returns `true` if all elements pass the predicate check,
 *  else `false`.
 */
function arrayEvery(array, predicate) {
  var index = -1,
      length = array == null ? 0 : array.length;

  while (++index < length) {
    if (!predicate(array[index], index, array)) {
      return false;
    }
  }
  return true;
}

/**
 * A specialized version of `_.filter` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} predicate The function invoked per iteration.
 * @returns {Array} Returns the new filtered array.
 */
function arrayFilter(array, predicate) {
  var index = -1,
      length = array == null ? 0 : array.length,
      resIndex = 0,
      result = [];

  while (++index < length) {
    var value = array[index];
    if (predicate(value, index, array)) {
      result[resIndex++] = value;
    }
  }
  return result;
}

/**
 * A specialized version of `_.includes` for arrays without support for
 * specifying an index to search from.
 *
 * @private
 * @param {Array} [array] The array to inspect.
 * @param {*} target The value to search for.
 * @returns {boolean} Returns `true` if `target` is found, else `false`.
 */
function arrayIncludes(array, value) {
  var length = array == null ? 0 : array.length;
  return !!length && baseIndexOf(array, value, 0) > -1;
}

/**
 * This function is like `arrayIncludes` except that it accepts a comparator.
 *
 * @private
 * @param {Array} [array] The array to inspect.
 * @param {*} target The value to search for.
 * @param {Function} comparator The comparator invoked per element.
 * @returns {boolean} Returns `true` if `target` is found, else `false`.
 */
function arrayIncludesWith(array, value, comparator) {
  var index = -1,
      length = array == null ? 0 : array.length;

  while (++index < length) {
    if (comparator(value, array[index])) {
      return true;
    }
  }
  return false;
}

/**
 * A specialized version of `_.map` for arrays without support for iteratee
 * shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {Array} Returns the new mapped array.
 */
function arrayMap(array, iteratee) {
  var index = -1,
      length = array == null ? 0 : array.length,
      result = Array(length);

  while (++index < length) {
    result[index] = iteratee(array[index], index, array);
  }
  return result;
}

/**
 * Appends the elements of `values` to `array`.
 *
 * @private
 * @param {Array} array The array to modify.
 * @param {Array} values The values to append.
 * @returns {Array} Returns `array`.
 */
function arrayPush(array, values) {
  var index = -1,
      length = values.length,
      offset = array.length;

  while (++index < length) {
    array[offset + index] = values[index];
  }
  return array;
}

/**
 * A specialized version of `_.reduce` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @param {*} [accumulator] The initial value.
 * @param {boolean} [initAccum] Specify using the first element of `array` as
 *  the initial value.
 * @returns {*} Returns the accumulated value.
 */
function arrayReduce(array, iteratee, accumulator, initAccum) {
  var index = -1,
      length = array == null ? 0 : array.length;

  if (initAccum && length) {
    accumulator = array[++index];
  }
  while (++index < length) {
    accumulator = iteratee(accumulator, array[index], index, array);
  }
  return accumulator;
}

/**
 * A specialized version of `_.reduceRight` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @param {*} [accumulator] The initial value.
 * @param {boolean} [initAccum] Specify using the last element of `array` as
 *  the initial value.
 * @returns {*} Returns the accumulated value.
 */
function arrayReduceRight(array, iteratee, accumulator, initAccum) {
  var length = array == null ? 0 : array.length;
  if (initAccum && length) {
    accumulator = array[--length];
  }
  while (length--) {
    accumulator = iteratee(accumulator, array[length], length, array);
  }
  return accumulator;
}

/**
 * A specialized version of `_.some` for arrays without support for iteratee
 * shorthands.
 *
 * @private
 * @param {Array} [array] The array to iterate over.
 * @param {Function} predicate The function invoked per iteration.
 * @returns {boolean} Returns `true` if any element passes the predicate check,
 *  else `false`.
 */
function arraySome(array, predicate) {
  var index = -1,
      length = array == null ? 0 : array.length;

  while (++index < length) {
    if (predicate(array[index], index, array)) {
      return true;
    }
  }
  return false;
}

/**
 * Gets the size of an ASCII `string`.
 *
 * @private
 * @param {string} string The string inspect.
 * @returns {number} Returns the string size.
 */
var asciiSize = baseProperty('length');

/**
 * Converts an ASCII `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function asciiToArray(string) {
  return string.split('');
}

/**
 * Splits an ASCII `string` into an array of its words.
 *
 * @private
 * @param {string} The string to inspect.
 * @returns {Array} Returns the words of `string`.
 */
function asciiWords(string) {
  return string.match(reAsciiWord) || [];
}

/**
 * The base implementation of methods like `_.findKey` and `_.findLastKey`,
 * without support for iteratee shorthands, which iterates over `collection`
 * using `eachFunc`.
 *
 * @private
 * @param {Array|Object} collection The collection to inspect.
 * @param {Function} predicate The function invoked per iteration.
 * @param {Function} eachFunc The function to iterate over `collection`.
 * @returns {*} Returns the found element or its key, else `undefined`.
 */
function baseFindKey(collection, predicate, eachFunc) {
  var result;
  eachFunc(collection, function(value, key, collection) {
    if (predicate(value, key, collection)) {
      result = key;
      return false;
    }
  });
  return result;
}

/**
 * The base implementation of `_.findIndex` and `_.findLastIndex` without
 * support for iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {Function} predicate The function invoked per iteration.
 * @param {number} fromIndex The index to search from.
 * @param {boolean} [fromRight] Specify iterating from right to left.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function baseFindIndex(array, predicate, fromIndex, fromRight) {
  var length = array.length,
      index = fromIndex + (fromRight ? 1 : -1);

  while ((fromRight ? index-- : ++index < length)) {
    if (predicate(array[index], index, array)) {
      return index;
    }
  }
  return -1;
}

/**
 * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function baseIndexOf(array, value, fromIndex) {
  return value === value
    ? strictIndexOf(array, value, fromIndex)
    : baseFindIndex(array, baseIsNaN, fromIndex);
}

/**
 * This function is like `baseIndexOf` except that it accepts a comparator.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @param {Function} comparator The comparator invoked per element.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function baseIndexOfWith(array, value, fromIndex, comparator) {
  var index = fromIndex - 1,
      length = array.length;

  while (++index < length) {
    if (comparator(array[index], value)) {
      return index;
    }
  }
  return -1;
}

/**
 * The base implementation of `_.isNaN` without support for number objects.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
 */
function baseIsNaN(value) {
  return value !== value;
}

/**
 * The base implementation of `_.mean` and `_.meanBy` without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {number} Returns the mean.
 */
function baseMean(array, iteratee) {
  var length = array == null ? 0 : array.length;
  return length ? (baseSum(array, iteratee) / length) : NAN;
}

/**
 * The base implementation of `_.property` without support for deep paths.
 *
 * @private
 * @param {string} key The key of the property to get.
 * @returns {Function} Returns the new accessor function.
 */
function baseProperty(key) {
  return function(object) {
    return object == null ? undefined : object[key];
  };
}

/**
 * The base implementation of `_.propertyOf` without support for deep paths.
 *
 * @private
 * @param {Object} object The object to query.
 * @returns {Function} Returns the new accessor function.
 */
function basePropertyOf(object) {
  return function(key) {
    return object == null ? undefined : object[key];
  };
}

/**
 * The base implementation of `_.reduce` and `_.reduceRight`, without support
 * for iteratee shorthands, which iterates over `collection` using `eachFunc`.
 *
 * @private
 * @param {Array|Object} collection The collection to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @param {*} accumulator The initial value.
 * @param {boolean} initAccum Specify using the first or last element of
 *  `collection` as the initial value.
 * @param {Function} eachFunc The function to iterate over `collection`.
 * @returns {*} Returns the accumulated value.
 */
function baseReduce(collection, iteratee, accumulator, initAccum, eachFunc) {
  eachFunc(collection, function(value, index, collection) {
    accumulator = initAccum
      ? (initAccum = false, value)
      : iteratee(accumulator, value, index, collection);
  });
  return accumulator;
}

/**
 * The base implementation of `_.sortBy` which uses `comparer` to define the
 * sort order of `array` and replaces criteria objects with their corresponding
 * values.
 *
 * @private
 * @param {Array} array The array to sort.
 * @param {Function} comparer The function to define sort order.
 * @returns {Array} Returns `array`.
 */
function baseSortBy(array, comparer) {
  var length = array.length;

  array.sort(comparer);
  while (length--) {
    array[length] = array[length].value;
  }
  return array;
}

/**
 * The base implementation of `_.sum` and `_.sumBy` without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {number} Returns the sum.
 */
function baseSum(array, iteratee) {
  var result,
      index = -1,
      length = array.length;

  while (++index < length) {
    var current = iteratee(array[index]);
    if (current !== undefined) {
      result = result === undefined ? current : (result + current);
    }
  }
  return result;
}

/**
 * The base implementation of `_.times` without support for iteratee shorthands
 * or max array length checks.
 *
 * @private
 * @param {number} n The number of times to invoke `iteratee`.
 * @param {Function} iteratee The function invoked per iteration.
 * @returns {Array} Returns the array of results.
 */
function baseTimes(n, iteratee) {
  var index = -1,
      result = Array(n);

  while (++index < n) {
    result[index] = iteratee(index);
  }
  return result;
}

/**
 * The base implementation of `_.toPairs` and `_.toPairsIn` which creates an array
 * of key-value pairs for `object` corresponding to the property names of `props`.
 *
 * @private
 * @param {Object} object The object to query.
 * @param {Array} props The property names to get values for.
 * @returns {Object} Returns the key-value pairs.
 */
function baseToPairs(object, props) {
  return arrayMap(props, function(key) {
    return [key, object[key]];
  });
}

/**
 * The base implementation of `_.unary` without support for storing metadata.
 *
 * @private
 * @param {Function} func The function to cap arguments for.
 * @returns {Function} Returns the new capped function.
 */
function baseUnary(func) {
  return function(value) {
    return func(value);
  };
}

/**
 * The base implementation of `_.values` and `_.valuesIn` which creates an
 * array of `object` property values corresponding to the property names
 * of `props`.
 *
 * @private
 * @param {Object} object The object to query.
 * @param {Array} props The property names to get values for.
 * @returns {Object} Returns the array of property values.
 */
function baseValues(object, props) {
  return arrayMap(props, function(key) {
    return object[key];
  });
}

/**
 * Checks if a `cache` value for `key` exists.
 *
 * @private
 * @param {Object} cache The cache to query.
 * @param {string} key The key of the entry to check.
 * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
 */
function cacheHas(cache, key) {
  return cache.has(key);
}

/**
 * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol
 * that is not found in the character symbols.
 *
 * @private
 * @param {Array} strSymbols The string symbols to inspect.
 * @param {Array} chrSymbols The character symbols to find.
 * @returns {number} Returns the index of the first unmatched string symbol.
 */
function charsStartIndex(strSymbols, chrSymbols) {
  var index = -1,
      length = strSymbols.length;

  while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
  return index;
}

/**
 * Used by `_.trim` and `_.trimEnd` to get the index of the last string symbol
 * that is not found in the character symbols.
 *
 * @private
 * @param {Array} strSymbols The string symbols to inspect.
 * @param {Array} chrSymbols The character symbols to find.
 * @returns {number} Returns the index of the last unmatched string symbol.
 */
function charsEndIndex(strSymbols, chrSymbols) {
  var index = strSymbols.length;

  while (index-- && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
  return index;
}

/**
 * Gets the number of `placeholder` occurrences in `array`.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} placeholder The placeholder to search for.
 * @returns {number} Returns the placeholder count.
 */
function countHolders(array, placeholder) {
  var length = array.length,
      result = 0;

  while (length--) {
    if (array[length] === placeholder) {
      ++result;
    }
  }
  return result;
}

/**
 * Used by `_.deburr` to convert Latin-1 Supplement and Latin Extended-A
 * letters to basic Latin letters.
 *
 * @private
 * @param {string} letter The matched letter to deburr.
 * @returns {string} Returns the deburred letter.
 */
var deburrLetter = basePropertyOf(deburredLetters);

/**
 * Used by `_.escape` to convert characters to HTML entities.
 *
 * @private
 * @param {string} chr The matched character to escape.
 * @returns {string} Returns the escaped character.
 */
var escapeHtmlChar = basePropertyOf(htmlEscapes);

/**
 * Used by `_.template` to escape characters for inclusion in compiled string literals.
 *
 * @private
 * @param {string} chr The matched character to escape.
 * @returns {string} Returns the escaped character.
 */
function escapeStringChar(chr) {
  return '\\' + stringEscapes[chr];
}

/**
 * Gets the value at `key` of `object`.
 *
 * @private
 * @param {Object} [object] The object to query.
 * @param {string} key The key of the property to get.
 * @returns {*} Returns the property value.
 */
function getValue(object, key) {
  return object == null ? undefined : object[key];
}

/**
 * Checks if `string` contains Unicode symbols.
 *
 * @private
 * @param {string} string The string to inspect.
 * @returns {boolean} Returns `true` if a symbol is found, else `false`.
 */
function hasUnicode(string) {
  return reHasUnicode.test(string);
}

/**
 * Checks if `string` contains a word composed of Unicode symbols.
 *
 * @private
 * @param {string} string The string to inspect.
 * @returns {boolean} Returns `true` if a word is found, else `false`.
 */
function hasUnicodeWord(string) {
  return reHasUnicodeWord.test(string);
}

/**
 * Converts `iterator` to an array.
 *
 * @private
 * @param {Object} iterator The iterator to convert.
 * @returns {Array} Returns the converted array.
 */
function iteratorToArray(iterator) {
  var data,
      result = [];

  while (!(data = iterator.next()).done) {
    result.push(data.value);
  }
  return result;
}

/**
 * Converts `map` to its key-value pairs.
 *
 * @private
 * @param {Object} map The map to convert.
 * @returns {Array} Returns the key-value pairs.
 */
function mapToArray(map) {
  var index = -1,
      result = Array(map.size);

  map.forEach(function(value, key) {
    result[++index] = [key, value];
  });
  return result;
}

/**
 * Creates a unary function that invokes `func` with its argument transformed.
 *
 * @private
 * @param {Function} func The function to wrap.
 * @param {Function} transform The argument transform.
 * @returns {Function} Returns the new function.
 */
function overArg(func, transform) {
  return function(arg) {
    return func(transform(arg));
  };
}

/**
 * Replaces all `placeholder` elements in `array` with an internal placeholder
 * and returns an array of their indexes.
 *
 * @private
 * @param {Array} array The array to modify.
 * @param {*} placeholder The placeholder to replace.
 * @returns {Array} Returns the new array of placeholder indexes.
 */
function replaceHolders(array, placeholder) {
  var index = -1,
      length = array.length,
      resIndex = 0,
      result = [];

  while (++index < length) {
    var value = array[index];
    if (value === placeholder || value === PLACEHOLDER) {
      array[index] = PLACEHOLDER;
      result[resIndex++] = index;
    }
  }
  return result;
}

/**
 * Converts `set` to an array of its values.
 *
 * @private
 * @param {Object} set The set to convert.
 * @returns {Array} Returns the values.
 */
function setToArray(set) {
  var index = -1,
      result = Array(set.size);

  set.forEach(function(value) {
    result[++index] = value;
  });
  return result;
}

/**
 * Converts `set` to its value-value pairs.
 *
 * @private
 * @param {Object} set The set to convert.
 * @returns {Array} Returns the value-value pairs.
 */
function setToPairs(set) {
  var index = -1,
      result = Array(set.size);

  set.forEach(function(value) {
    result[++index] = [value, value];
  });
  return result;
}

/**
 * A specialized version of `_.indexOf` which performs strict equality
 * comparisons of values, i.e. `===`.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function strictIndexOf(array, value, fromIndex) {
  var index = fromIndex - 1,
      length = array.length;

  while (++index < length) {
    if (array[index] === value) {
      return index;
    }
  }
  return -1;
}

/**
 * A specialized version of `_.lastIndexOf` which performs strict equality
 * comparisons of values, i.e. `===`.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function strictLastIndexOf(array, value, fromIndex) {
  var index = fromIndex + 1;
  while (index--) {
    if (array[index] === value) {
      return index;
    }
  }
  return index;
}

/**
 * Gets the number of symbols in `string`.
 *
 * @private
 * @param {string} string The string to inspect.
 * @returns {number} Returns the string size.
 */
function stringSize(string) {
  return hasUnicode(string)
    ? unicodeSize(string)
    : asciiSize(string);
}

/**
 * Converts `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function stringToArray(string) {
  return hasUnicode(string)
    ? unicodeToArray(string)
    : asciiToArray(string);
}

/**
 * Used by `_.unescape` to convert HTML entities to characters.
 *
 * @private
 * @param {string} chr The matched character to unescape.
 * @returns {string} Returns the unescaped character.
 */
var unescapeHtmlChar = basePropertyOf(htmlUnescapes);

/**
 * Gets the size of a Unicode `string`.
 *
 * @private
 * @param {string} string The string inspect.
 * @returns {number} Returns the string size.
 */
function unicodeSize(string) {
  var result = reUnicode.lastIndex = 0;
  while (reUnicode.test(string)) {
    ++result;
  }
  return result;
}

/**
 * Converts a Unicode `string` to an array.
 *
 * @private
 * @param {string} string The string to convert.
 * @returns {Array} Returns the converted array.
 */
function unicodeToArray(string) {
  return string.match(reUnicode) || [];
}

/**
 * Splits a Unicode `string` into an array of its words.
 *
 * @private
 * @param {string} The string to inspect.
 * @returns {Array} Returns the words of `string`.
 */
function unicodeWords(string) {
  return string.match(reUnicodeWord) || [];
}

/*--------------------------------------------------------------------------*/

/**
 * Create a new pristine `lodash` function using the `context` object.
 *
 * @static
 * @memberOf _
 * @since 1.1.0
 * @category Util
 * @param {Object} [context=root] The context object.
 * @returns {Function} Returns a new `lodash` function.
 * @example
 *
 * _.mixin({ 'foo': _.constant('foo') });
 *
 * var lodash = _.runInContext();
 * lodash.mixin({ 'bar': lodash.constant('bar') });
 *
 * _.isFunction(_.foo);
 * // => true
 * _.isFunction(_.bar);
 * // => false
 *
 * lodash.isFunction(lodash.foo);
 * // => false
 * lodash.isFunction(lodash.bar);
 * // => true
 *
 * // Create a suped-up `defer` in Node.js.
 * var defer = _.runInContext({ 'setTimeout': setImmediate }).defer;
 */
var runInContext = (function runInContext(context) {
  context = context == null ? root : _.defaults(root.Object(), context, _.pick(root, contextProps));

  /** Built-in constructor references. */
  var Array = context.Array,
      Date = context.Date,
      Error = context.Error,
      Function = context.Function,
      Math = context.Math,
      Object = context.Object,
      RegExp = context.RegExp,
      String = context.String,
      TypeError = context.TypeError;

  /** Used for built-in method references. */
  var arrayProto = Array.prototype,
      funcProto = Function.prototype,
      objectProto = Object.prototype;

  /** Used to detect overreaching core-js shims. */
  var coreJsData = context['__core-js_shared__'];

  /** Used to resolve the decompiled source of functions. */
  var funcToString = funcProto.toString;

  /** Used to check objects for own properties. */
  var hasOwnProperty = objectProto.hasOwnProperty;

  /** Used to generate unique IDs. */
  var idCounter = 0;

  /** Used to detect methods masquerading as native. */
  var maskSrcKey = (function() {
    var uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || '');
    return uid ? ('Symbol(src)_1.' + uid) : '';
  }());

  /**
   * Used to resolve the
   * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
   * of values.
   */
  var nativeObjectToString = objectProto.toString;

  /** Used to infer the `Object` constructor. */
  var objectCtorString = funcToString.call(Object);

  /** Used to restore the original `_` reference in `_.noConflict`. */
  var oldDash = root._;

  /** Used to detect if a method is native. */
  var reIsNative = RegExp('^' +
    funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&')
    .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
  );

  /** Built-in value references. */
  var Buffer = moduleExports ? context.Buffer : undefined,
      Symbol = context.Symbol,
      Uint8Array = context.Uint8Array,
      allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined,
      getPrototype = overArg(Object.getPrototypeOf, Object),
      objectCreate = Object.create,
      propertyIsEnumerable = objectProto.propertyIsEnumerable,
      splice = arrayProto.splice,
      spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined,
      symIterator = Symbol ? Symbol.iterator : undefined,
      symToStringTag = Symbol ? Symbol.toStringTag : undefined;

  var defineProperty = (function() {
    try {
      var func = getNative(Object, 'defineProperty');
      func({}, '', {});
      return func;
    } catch (e) {}
  }());

  /** Mocked built-ins. */
  var ctxClearTimeout = context.clearTimeout !== root.clearTimeout && context.clearTimeout,
      ctxNow = Date && Date.now !== root.Date.now && Date.now,
      ctxSetTimeout = context.setTimeout !== root.setTimeout && context.setTimeout;

  /* Built-in method references for those with the same name as other `lodash` methods. */
  var nativeCeil = Math.ceil,
      nativeFloor = Math.floor,
      nativeGetSymbols = Object.getOwnPropertySymbols,
      nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined,
      nativeIsFinite = context.isFinite,
      nativeJoin = arrayProto.join,
      nativeKeys = overArg(Object.keys, Object),
      nativeMax = Math.max,
      nativeMin = Math.min,
      nativeNow = Date.now,
      nativeParseInt = context.parseInt,
      nativeRandom = Math.random,
      nativeReverse = arrayProto.reverse;

  /* Built-in method references that are verified to be native. */
  var DataView = getNative(context, 'DataView'),
      Map = getNative(context, 'Map'),
      Promise = getNative(context, 'Promise'),
      Set = getNative(context, 'Set'),
      WeakMap = getNative(context, 'WeakMap'),
      nativeCreate = getNative(Object, 'create');

  /** Used to store function metadata. */
  var metaMap = WeakMap && new WeakMap;

  /** Used to lookup unminified function names. */
  var realNames = {};

  /** Used to detect maps, sets, and weakmaps. */
  var dataViewCtorString = toSource(DataView),
      mapCtorString = toSource(Map),
      promiseCtorString = toSource(Promise),
      setCtorString = toSource(Set),
      weakMapCtorString = toSource(WeakMap);

  /** Used to convert symbols to primitives and strings. */
  var symbolProto = Symbol ? Symbol.prototype : undefined,
      symbolValueOf = symbolProto ? symbolProto.valueOf : undefined,
      symbolToString = symbolProto ? symbolProto.toString : undefined;

  /*------------------------------------------------------------------------*/

  /**
   * Creates a `lodash` object which wraps `value` to enable implicit method
   * chain sequences. Methods that operate on and return arrays, collections,
   * and functions can be chained together. Methods that retrieve a single value
   * or may return a primitive value will automatically end the chain sequence
   * and return the unwrapped value. Otherwise, the value must be unwrapped
   * with `_#value`.
   *
   * Explicit chain sequences, which must be unwrapped with `_#value`, may be
   * enabled using `_.chain`.
   *
   * The execution of chained methods is lazy, that is, it's deferred until
   * `_#value` is implicitly or explicitly called.
   *
   * Lazy evaluation allows several methods to support shortcut fusion.
   * Shortcut fusion is an optimization to merge iteratee calls; this avoids
   * the creation of intermediate arrays and can greatly reduce the number of
   * iteratee executions. Sections of a chain sequence qualify for shortcut
   * fusion if the section is applied to an array and iteratees accept only
   * one argument. The heuristic for whether a section qualifies for shortcut
   * fusion is subject to change.
   *
   * Chaining is supported in custom builds as long as the `_#value` method is
   * directly or indirectly included in the build.
   *
   * In addition to lodash methods, wrappers have `Array` and `String` methods.
   *
   * The wrapper `Array` methods are:
   * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift`
   *
   * The wrapper `String` methods are:
   * `replace` and `split`
   *
   * The wrapper methods that support shortcut fusion are:
   * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`,
   * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`,
   * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray`
   *
   * The chainable wrapper methods are:
   * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`,
   * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`,
   * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`,
   * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`,
   * `difference`, `differenceBy`, `differenceWith`, `drop`, `dropRight`,
   * `dropRightWhile`, `dropWhile`, `extend`, `extendWith`, `fill`, `filter`,
   * `flatMap`, `flatMapDeep`, `flatMapDepth`, `flatten`, `flattenDeep`,
   * `flattenDepth`, `flip`, `flow`, `flowRight`, `fromPairs`, `functions`,
   * `functionsIn`, `groupBy`, `initial`, `intersection`, `intersectionBy`,
   * `intersectionWith`, `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`,
   * `keys`, `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`,
   * `memoize`, `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`,
   * `nthArg`, `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`,
   * `overEvery`, `overSome`, `partial`, `partialRight`, `partition`, `pick`,
   * `pickBy`, `plant`, `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`,
   * `pullAllWith`, `pullAt`, `push`, `range`, `rangeRight`, `rearg`, `reject`,
   * `remove`, `rest`, `reverse`, `sampleSize`, `set`, `setWith`, `shuffle`,
   * `slice`, `sort`, `sortBy`, `splice`, `spread`, `tail`, `take`, `takeRight`,
   * `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `toArray`,
   * `toPairs`, `toPairsIn`, `toPath`, `toPlainObject`, `transform`, `unary`,
   * `union`, `unionBy`, `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`,
   * `unshift`, `unzip`, `unzipWith`, `update`, `updateWith`, `values`,
   * `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, `xorWith`, `zip`,
   * `zipObject`, `zipObjectDeep`, and `zipWith`
   *
   * The wrapper methods that are **not** chainable by default are:
   * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`,
   * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `conformsTo`, `deburr`,
   * `defaultTo`, `divide`, `each`, `eachRight`, `endsWith`, `eq`, `escape`,
   * `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`,
   * `findLastIndex`, `findLastKey`, `first`, `floor`, `forEach`, `forEachRight`,
   * `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`,
   * `hasIn`, `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`,
   * `isArguments`, `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`,
   * `isBoolean`, `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`,
   * `isEqualWith`, `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`,
   * `isMap`, `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`,
   * `isNumber`, `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`,
   * `isSafeInteger`, `isSet`, `isString`, `isUndefined`, `isTypedArray`,
   * `isWeakMap`, `isWeakSet`, `join`, `kebabCase`, `last`, `lastIndexOf`,
   * `lowerCase`, `lowerFirst`, `lt`, `lte`, `max`, `maxBy`, `mean`, `meanBy`,
   * `min`, `minBy`, `multiply`, `noConflict`, `noop`, `now`, `nth`, `pad`,
   * `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`,
   * `repeat`, `result`, `round`, `runInContext`, `sample`, `shift`, `size`,
   * `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, `sortedLastIndex`,
   * `sortedLastIndexBy`, `startCase`, `startsWith`, `stubArray`, `stubFalse`,
   * `stubObject`, `stubString`, `stubTrue`, `subtract`, `sum`, `sumBy`,
   * `template`, `times`, `toFinite`, `toInteger`, `toJSON`, `toLength`,
   * `toLower`, `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`,
   * `trimEnd`, `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`,
   * `upperFirst`, `value`, and `words`
   *
   * @name _
   * @constructor
   * @category Seq
   * @param {*} value The value to wrap in a `lodash` instance.
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var wrapped = _([1, 2, 3]);
   *
   * // Returns an unwrapped value.
   * wrapped.reduce(_.add);
   * // => 6
   *
   * // Returns a wrapped value.
   * var squares = wrapped.map(square);
   *
   * _.isArray(squares);
   * // => false
   *
   * _.isArray(squares.value());
   * // => true
   */
  function lodash(value) {
    if (isObjectLike(value) && !isArray(value) && !(value instanceof LazyWrapper)) {
      if (value instanceof LodashWrapper) {
        return value;
      }
      if (hasOwnProperty.call(value, '__wrapped__')) {
        return wrapperClone(value);
      }
    }
    return new LodashWrapper(value);
  }

  /**
   * The base implementation of `_.create` without support for assigning
   * properties to the created object.
   *
   * @private
   * @param {Object} proto The object to inherit from.
   * @returns {Object} Returns the new object.
   */
  var baseCreate = (function() {
    function object() {}
    return function(proto) {
      if (!isObject(proto)) {
        return {};
      }
      if (objectCreate) {
        return objectCreate(proto);
      }
      object.prototype = proto;
      var result = new object;
      object.prototype = undefined;
      return result;
    };
  }());

  /**
   * The function whose prototype chain sequence wrappers inherit from.
   *
   * @private
   */
  function baseLodash() {
    // No operation performed.
  }

  /**
   * The base constructor for creating `lodash` wrapper objects.
   *
   * @private
   * @param {*} value The value to wrap.
   * @param {boolean} [chainAll] Enable explicit method chain sequences.
   */
  function LodashWrapper(value, chainAll) {
    this.__wrapped__ = value;
    this.__actions__ = [];
    this.__chain__ = !!chainAll;
    this.__index__ = 0;
    this.__values__ = undefined;
  }

  /**
   * By default, the template delimiters used by lodash are like those in
   * embedded Ruby (ERB) as well as ES2015 template strings. Change the
   * following template settings to use alternative delimiters.
   *
   * @static
   * @memberOf _
   * @type {Object}
   */
  lodash.templateSettings = {

    /**
     * Used to detect `data` property values to be HTML-escaped.
     *
     * @memberOf _.templateSettings
     * @type {RegExp}
     */
    'escape': reEscape,

    /**
     * Used to detect code to be evaluated.
     *
     * @memberOf _.templateSettings
     * @type {RegExp}
     */
    'evaluate': reEvaluate,

    /**
     * Used to detect `data` property values to inject.
     *
     * @memberOf _.templateSettings
     * @type {RegExp}
     */
    'interpolate': reInterpolate,

    /**
     * Used to reference the data object in the template text.
     *
     * @memberOf _.templateSettings
     * @type {string}
     */
    'variable': '',

    /**
     * Used to import variables into the compiled template.
     *
     * @memberOf _.templateSettings
     * @type {Object}
     */
    'imports': {

      /**
       * A reference to the `lodash` function.
       *
       * @memberOf _.templateSettings.imports
       * @type {Function}
       */
      '_': lodash
    }
  };

  // Ensure wrappers are instances of `baseLodash`.
  lodash.prototype = baseLodash.prototype;
  lodash.prototype.constructor = lodash;

  LodashWrapper.prototype = baseCreate(baseLodash.prototype);
  LodashWrapper.prototype.constructor = LodashWrapper;

  /*------------------------------------------------------------------------*/

  /**
   * Creates a lazy wrapper object which wraps `value` to enable lazy evaluation.
   *
   * @private
   * @constructor
   * @param {*} value The value to wrap.
   */
  function LazyWrapper(value) {
    this.__wrapped__ = value;
    this.__actions__ = [];
    this.__dir__ = 1;
    this.__filtered__ = false;
    this.__iteratees__ = [];
    this.__takeCount__ = MAX_ARRAY_LENGTH;
    this.__views__ = [];
  }

  /**
   * Creates a clone of the lazy wrapper object.
   *
   * @private
   * @name clone
   * @memberOf LazyWrapper
   * @returns {Object} Returns the cloned `LazyWrapper` object.
   */
  function lazyClone() {
    var result = new LazyWrapper(this.__wrapped__);
    result.__actions__ = copyArray(this.__actions__);
    result.__dir__ = this.__dir__;
    result.__filtered__ = this.__filtered__;
    result.__iteratees__ = copyArray(this.__iteratees__);
    result.__takeCount__ = this.__takeCount__;
    result.__views__ = copyArray(this.__views__);
    return result;
  }

  /**
   * Reverses the direction of lazy iteration.
   *
   * @private
   * @name reverse
   * @memberOf LazyWrapper
   * @returns {Object} Returns the new reversed `LazyWrapper` object.
   */
  function lazyReverse() {
    if (this.__filtered__) {
      var result = new LazyWrapper(this);
      result.__dir__ = -1;
      result.__filtered__ = true;
    } else {
      result = this.clone();
      result.__dir__ *= -1;
    }
    return result;
  }

  /**
   * Extracts the unwrapped value from its lazy wrapper.
   *
   * @private
   * @name value
   * @memberOf LazyWrapper
   * @returns {*} Returns the unwrapped value.
   */
  function lazyValue() {
    var array = this.__wrapped__.value(),
        dir = this.__dir__,
        isArr = isArray(array),
        isRight = dir < 0,
        arrLength = isArr ? array.length : 0,
        view = getView(0, arrLength, this.__views__),
        start = view.start,
        end = view.end,
        length = end - start,
        index = isRight ? end : (start - 1),
        iteratees = this.__iteratees__,
        iterLength = iteratees.length,
        resIndex = 0,
        takeCount = nativeMin(length, this.__takeCount__);

    if (!isArr || (!isRight && arrLength == length && takeCount == length)) {
      return baseWrapperValue(array, this.__actions__);
    }
    var result = [];

    outer:
    while (length-- && resIndex < takeCount) {
      index += dir;

      var iterIndex = -1,
          value = array[index];

      while (++iterIndex < iterLength) {
        var data = iteratees[iterIndex],
            iteratee = data.iteratee,
            type = data.type,
            computed = iteratee(value);

        if (type == LAZY_MAP_FLAG) {
          value = computed;
        } else if (!computed) {
          if (type == LAZY_FILTER_FLAG) {
            continue outer;
          } else {
            break outer;
          }
        }
      }
      result[resIndex++] = value;
    }
    return result;
  }

  // Ensure `LazyWrapper` is an instance of `baseLodash`.
  LazyWrapper.prototype = baseCreate(baseLodash.prototype);
  LazyWrapper.prototype.constructor = LazyWrapper;

  /*------------------------------------------------------------------------*/

  /**
   * Creates a hash object.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function Hash(entries) {
    var index = -1,
        length = entries == null ? 0 : entries.length;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the hash.
   *
   * @private
   * @name clear
   * @memberOf Hash
   */
  function hashClear() {
    this.__data__ = nativeCreate ? nativeCreate(null) : {};
    this.size = 0;
  }

  /**
   * Removes `key` and its value from the hash.
   *
   * @private
   * @name delete
   * @memberOf Hash
   * @param {Object} hash The hash to modify.
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function hashDelete(key) {
    var result = this.has(key) && delete this.__data__[key];
    this.size -= result ? 1 : 0;
    return result;
  }

  /**
   * Gets the hash value for `key`.
   *
   * @private
   * @name get
   * @memberOf Hash
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function hashGet(key) {
    var data = this.__data__;
    if (nativeCreate) {
      var result = data[key];
      return result === HASH_UNDEFINED ? undefined : result;
    }
    return hasOwnProperty.call(data, key) ? data[key] : undefined;
  }

  /**
   * Checks if a hash value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf Hash
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function hashHas(key) {
    var data = this.__data__;
    return nativeCreate ? (data[key] !== undefined) : hasOwnProperty.call(data, key);
  }

  /**
   * Sets the hash `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf Hash
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the hash instance.
   */
  function hashSet(key, value) {
    var data = this.__data__;
    this.size += this.has(key) ? 0 : 1;
    data[key] = (nativeCreate && value === undefined) ? HASH_UNDEFINED : value;
    return this;
  }

  // Add methods to `Hash`.
  Hash.prototype.clear = hashClear;
  Hash.prototype['delete'] = hashDelete;
  Hash.prototype.get = hashGet;
  Hash.prototype.has = hashHas;
  Hash.prototype.set = hashSet;

  /*------------------------------------------------------------------------*/

  /**
   * Creates an list cache object.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function ListCache(entries) {
    var index = -1,
        length = entries == null ? 0 : entries.length;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the list cache.
   *
   * @private
   * @name clear
   * @memberOf ListCache
   */
  function listCacheClear() {
    this.__data__ = [];
    this.size = 0;
  }

  /**
   * Removes `key` and its value from the list cache.
   *
   * @private
   * @name delete
   * @memberOf ListCache
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function listCacheDelete(key) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    if (index < 0) {
      return false;
    }
    var lastIndex = data.length - 1;
    if (index == lastIndex) {
      data.pop();
    } else {
      splice.call(data, index, 1);
    }
    --this.size;
    return true;
  }

  /**
   * Gets the list cache value for `key`.
   *
   * @private
   * @name get
   * @memberOf ListCache
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function listCacheGet(key) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    return index < 0 ? undefined : data[index][1];
  }

  /**
   * Checks if a list cache value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf ListCache
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function listCacheHas(key) {
    return assocIndexOf(this.__data__, key) > -1;
  }

  /**
   * Sets the list cache `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf ListCache
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the list cache instance.
   */
  function listCacheSet(key, value) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    if (index < 0) {
      ++this.size;
      data.push([key, value]);
    } else {
      data[index][1] = value;
    }
    return this;
  }

  // Add methods to `ListCache`.
  ListCache.prototype.clear = listCacheClear;
  ListCache.prototype['delete'] = listCacheDelete;
  ListCache.prototype.get = listCacheGet;
  ListCache.prototype.has = listCacheHas;
  ListCache.prototype.set = listCacheSet;

  /*------------------------------------------------------------------------*/

  /**
   * Creates a map cache object to store key-value pairs.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function MapCache(entries) {
    var index = -1,
        length = entries == null ? 0 : entries.length;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the map.
   *
   * @private
   * @name clear
   * @memberOf MapCache
   */
  function mapCacheClear() {
    this.size = 0;
    this.__data__ = {
      'hash': new Hash,
      'map': new (Map || ListCache),
      'string': new Hash
    };
  }

  /**
   * Removes `key` and its value from the map.
   *
   * @private
   * @name delete
   * @memberOf MapCache
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function mapCacheDelete(key) {
    var result = getMapData(this, key)['delete'](key);
    this.size -= result ? 1 : 0;
    return result;
  }

  /**
   * Gets the map value for `key`.
   *
   * @private
   * @name get
   * @memberOf MapCache
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function mapCacheGet(key) {
    return getMapData(this, key).get(key);
  }

  /**
   * Checks if a map value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf MapCache
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function mapCacheHas(key) {
    return getMapData(this, key).has(key);
  }

  /**
   * Sets the map `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf MapCache
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the map cache instance.
   */
  function mapCacheSet(key, value) {
    var data = getMapData(this, key),
        size = data.size;

    data.set(key, value);
    this.size += data.size == size ? 0 : 1;
    return this;
  }

  // Add methods to `MapCache`.
  MapCache.prototype.clear = mapCacheClear;
  MapCache.prototype['delete'] = mapCacheDelete;
  MapCache.prototype.get = mapCacheGet;
  MapCache.prototype.has = mapCacheHas;
  MapCache.prototype.set = mapCacheSet;

  /*------------------------------------------------------------------------*/

  /**
   *
   * Creates an array cache object to store unique values.
   *
   * @private
   * @constructor
   * @param {Array} [values] The values to cache.
   */
  function SetCache(values) {
    var index = -1,
        length = values == null ? 0 : values.length;

    this.__data__ = new MapCache;
    while (++index < length) {
      this.add(values[index]);
    }
  }

  /**
   * Adds `value` to the array cache.
   *
   * @private
   * @name add
   * @memberOf SetCache
   * @alias push
   * @param {*} value The value to cache.
   * @returns {Object} Returns the cache instance.
   */
  function setCacheAdd(value) {
    this.__data__.set(value, HASH_UNDEFINED);
    return this;
  }

  /**
   * Checks if `value` is in the array cache.
   *
   * @private
   * @name has
   * @memberOf SetCache
   * @param {*} value The value to search for.
   * @returns {number} Returns `true` if `value` is found, else `false`.
   */
  function setCacheHas(value) {
    return this.__data__.has(value);
  }

  // Add methods to `SetCache`.
  SetCache.prototype.add = SetCache.prototype.push = setCacheAdd;
  SetCache.prototype.has = setCacheHas;

  /*------------------------------------------------------------------------*/

  /**
   * Creates a stack cache object to store key-value pairs.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function Stack(entries) {
    var data = this.__data__ = new ListCache(entries);
    this.size = data.size;
  }

  /**
   * Removes all key-value entries from the stack.
   *
   * @private
   * @name clear
   * @memberOf Stack
   */
  function stackClear() {
    this.__data__ = new ListCache;
    this.size = 0;
  }

  /**
   * Removes `key` and its value from the stack.
   *
   * @private
   * @name delete
   * @memberOf Stack
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function stackDelete(key) {
    var data = this.__data__,
        result = data['delete'](key);

    this.size = data.size;
    return result;
  }

  /**
   * Gets the stack value for `key`.
   *
   * @private
   * @name get
   * @memberOf Stack
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function stackGet(key) {
    return this.__data__.get(key);
  }

  /**
   * Checks if a stack value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf Stack
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function stackHas(key) {
    return this.__data__.has(key);
  }

  /**
   * Sets the stack `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf Stack
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the stack cache instance.
   */
  function stackSet(key, value) {
    var data = this.__data__;
    if (data instanceof ListCache) {
      var pairs = data.__data__;
      if (!Map || (pairs.length < LARGE_ARRAY_SIZE - 1)) {
        pairs.push([key, value]);
        this.size = ++data.size;
        return this;
      }
      data = this.__data__ = new MapCache(pairs);
    }
    data.set(key, value);
    this.size = data.size;
    return this;
  }

  // Add methods to `Stack`.
  Stack.prototype.clear = stackClear;
  Stack.prototype['delete'] = stackDelete;
  Stack.prototype.get = stackGet;
  Stack.prototype.has = stackHas;
  Stack.prototype.set = stackSet;

  /*------------------------------------------------------------------------*/

  /**
   * Creates an array of the enumerable property names of the array-like `value`.
   *
   * @private
   * @param {*} value The value to query.
   * @param {boolean} inherited Specify returning inherited property names.
   * @returns {Array} Returns the array of property names.
   */
  function arrayLikeKeys(value, inherited) {
    var isArr = isArray(value),
        isArg = !isArr && isArguments(value),
        isBuff = !isArr && !isArg && isBuffer(value),
        isType = !isArr && !isArg && !isBuff && isTypedArray(value),
        skipIndexes = isArr || isArg || isBuff || isType,
        result = skipIndexes ? baseTimes(value.length, String) : [],
        length = result.length;

    for (var key in value) {
      if ((inherited || hasOwnProperty.call(value, key)) &&
          !(skipIndexes && (
             // Safari 9 has enumerable `arguments.length` in strict mode.
             key == 'length' ||
             // Node.js 0.10 has enumerable non-index properties on buffers.
             (isBuff && (key == 'offset' || key == 'parent')) ||
             // PhantomJS 2 has enumerable non-index properties on typed arrays.
             (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
             // Skip index properties.
             isIndex(key, length)
          ))) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * A specialized version of `_.sample` for arrays.
   *
   * @private
   * @param {Array} array The array to sample.
   * @returns {*} Returns the random element.
   */
  function arraySample(array) {
    var length = array.length;
    return length ? array[baseRandom(0, length - 1)] : undefined;
  }

  /**
   * A specialized version of `_.sampleSize` for arrays.
   *
   * @private
   * @param {Array} array The array to sample.
   * @param {number} n The number of elements to sample.
   * @returns {Array} Returns the random elements.
   */
  function arraySampleSize(array, n) {
    return shuffleSelf(copyArray(array), baseClamp(n, 0, array.length));
  }

  /**
   * A specialized version of `_.shuffle` for arrays.
   *
   * @private
   * @param {Array} array The array to shuffle.
   * @returns {Array} Returns the new shuffled array.
   */
  function arrayShuffle(array) {
    return shuffleSelf(copyArray(array));
  }

  /**
   * This function is like `assignValue` except that it doesn't assign
   * `undefined` values.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {string} key The key of the property to assign.
   * @param {*} value The value to assign.
   */
  function assignMergeValue(object, key, value) {
    if ((value !== undefined && !eq(object[key], value)) ||
        (value === undefined && !(key in object))) {
      baseAssignValue(object, key, value);
    }
  }

  /**
   * Assigns `value` to `key` of `object` if the existing value is not equivalent
   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {string} key The key of the property to assign.
   * @param {*} value The value to assign.
   */
  function assignValue(object, key, value) {
    var objValue = object[key];
    if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) ||
        (value === undefined && !(key in object))) {
      baseAssignValue(object, key, value);
    }
  }

  /**
   * Gets the index at which the `key` is found in `array` of key-value pairs.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} key The key to search for.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function assocIndexOf(array, key) {
    var length = array.length;
    while (length--) {
      if (eq(array[length][0], key)) {
        return length;
      }
    }
    return -1;
  }

  /**
   * Aggregates elements of `collection` on `accumulator` with keys transformed
   * by `iteratee` and values set by `setter`.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} setter The function to set `accumulator` values.
   * @param {Function} iteratee The iteratee to transform keys.
   * @param {Object} accumulator The initial aggregated object.
   * @returns {Function} Returns `accumulator`.
   */
  function baseAggregator(collection, setter, iteratee, accumulator) {
    baseEach(collection, function(value, key, collection) {
      setter(accumulator, value, iteratee(value), collection);
    });
    return accumulator;
  }

  /**
   * The base implementation of `_.assign` without support for multiple sources
   * or `customizer` functions.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @returns {Object} Returns `object`.
   */
  function baseAssign(object, source) {
    return object && copyObject(source, keys(source), object);
  }

  /**
   * The base implementation of `_.assignIn` without support for multiple sources
   * or `customizer` functions.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @returns {Object} Returns `object`.
   */
  function baseAssignIn(object, source) {
    return object && copyObject(source, keysIn(source), object);
  }

  /**
   * The base implementation of `assignValue` and `assignMergeValue` without
   * value checks.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {string} key The key of the property to assign.
   * @param {*} value The value to assign.
   */
  function baseAssignValue(object, key, value) {
    if (key == '__proto__' && defineProperty) {
      defineProperty(object, key, {
        'configurable': true,
        'enumerable': true,
        'value': value,
        'writable': true
      });
    } else {
      object[key] = value;
    }
  }

  /**
   * The base implementation of `_.at` without support for individual paths.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {string[]} paths The property paths to pick.
   * @returns {Array} Returns the picked elements.
   */
  function baseAt(object, paths) {
    var index = -1,
        length = paths.length,
        result = Array(length),
        skip = object == null;

    while (++index < length) {
      result[index] = skip ? undefined : get(object, paths[index]);
    }
    return result;
  }

  /**
   * The base implementation of `_.clamp` which doesn't coerce arguments.
   *
   * @private
   * @param {number} number The number to clamp.
   * @param {number} [lower] The lower bound.
   * @param {number} upper The upper bound.
   * @returns {number} Returns the clamped number.
   */
  function baseClamp(number, lower, upper) {
    if (number === number) {
      if (upper !== undefined) {
        number = number <= upper ? number : upper;
      }
      if (lower !== undefined) {
        number = number >= lower ? number : lower;
      }
    }
    return number;
  }

  /**
   * The base implementation of `_.clone` and `_.cloneDeep` which tracks
   * traversed objects.
   *
   * @private
   * @param {*} value The value to clone.
   * @param {boolean} bitmask The bitmask flags.
   *  1 - Deep clone
   *  2 - Flatten inherited properties
   *  4 - Clone symbols
   * @param {Function} [customizer] The function to customize cloning.
   * @param {string} [key] The key of `value`.
   * @param {Object} [object] The parent object of `value`.
   * @param {Object} [stack] Tracks traversed objects and their clone counterparts.
   * @returns {*} Returns the cloned value.
   */
  function baseClone(value, bitmask, customizer, key, object, stack) {
    var result,
        isDeep = bitmask & CLONE_DEEP_FLAG,
        isFlat = bitmask & CLONE_FLAT_FLAG,
        isFull = bitmask & CLONE_SYMBOLS_FLAG;

    if (customizer) {
      result = object ? customizer(value, key, object, stack) : customizer(value);
    }
    if (result !== undefined) {
      return result;
    }
    if (!isObject(value)) {
      return value;
    }
    var isArr = isArray(value);
    if (isArr) {
      result = initCloneArray(value);
      if (!isDeep) {
        return copyArray(value, result);
      }
    } else {
      var tag = getTag(value),
          isFunc = tag == funcTag || tag == genTag;

      if (isBuffer(value)) {
        return cloneBuffer(value, isDeep);
      }
      if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
        result = (isFlat || isFunc) ? {} : initCloneObject(value);
        if (!isDeep) {
          return isFlat
            ? copySymbolsIn(value, baseAssignIn(result, value))
            : copySymbols(value, baseAssign(result, value));
        }
      } else {
        if (!cloneableTags[tag]) {
          return object ? value : {};
        }
        result = initCloneByTag(value, tag, isDeep);
      }
    }
    // Check for circular references and return its corresponding clone.
    stack || (stack = new Stack);
    var stacked = stack.get(value);
    if (stacked) {
      return stacked;
    }
    stack.set(value, result);

    if (isSet(value)) {
      value.forEach(function(subValue) {
        result.add(baseClone(subValue, bitmask, customizer, subValue, value, stack));
      });
    } else if (isMap(value)) {
      value.forEach(function(subValue, key) {
        result.set(key, baseClone(subValue, bitmask, customizer, key, value, stack));
      });
    }

    var keysFunc = isFull
      ? (isFlat ? getAllKeysIn : getAllKeys)
      : (isFlat ? keysIn : keys);

    var props = isArr ? undefined : keysFunc(value);
    arrayEach(props || value, function(subValue, key) {
      if (props) {
        key = subValue;
        subValue = value[key];
      }
      // Recursively populate clone (susceptible to call stack limits).
      assignValue(result, key, baseClone(subValue, bitmask, customizer, key, value, stack));
    });
    return result;
  }

  /**
   * The base implementation of `_.conforms` which doesn't clone `source`.
   *
   * @private
   * @param {Object} source The object of property predicates to conform to.
   * @returns {Function} Returns the new spec function.
   */
  function baseConforms(source) {
    var props = keys(source);
    return function(object) {
      return baseConformsTo(object, source, props);
    };
  }

  /**
   * The base implementation of `_.conformsTo` which accepts `props` to check.
   *
   * @private
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property predicates to conform to.
   * @returns {boolean} Returns `true` if `object` conforms, else `false`.
   */
  function baseConformsTo(object, source, props) {
    var length = props.length;
    if (object == null) {
      return !length;
    }
    object = Object(object);
    while (length--) {
      var key = props[length],
          predicate = source[key],
          value = object[key];

      if ((value === undefined && !(key in object)) || !predicate(value)) {
        return false;
      }
    }
    return true;
  }

  /**
   * The base implementation of `_.delay` and `_.defer` which accepts `args`
   * to provide to `func`.
   *
   * @private
   * @param {Function} func The function to delay.
   * @param {number} wait The number of milliseconds to delay invocation.
   * @param {Array} args The arguments to provide to `func`.
   * @returns {number|Object} Returns the timer id or timeout object.
   */
  function baseDelay(func, wait, args) {
    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    return setTimeout(function() { func.apply(undefined, args); }, wait);
  }

  /**
   * The base implementation of methods like `_.difference` without support
   * for excluding multiple arrays or iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {Array} values The values to exclude.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of filtered values.
   */
  function baseDifference(array, values, iteratee, comparator) {
    var index = -1,
        includes = arrayIncludes,
        isCommon = true,
        length = array.length,
        result = [],
        valuesLength = values.length;

    if (!length) {
      return result;
    }
    if (iteratee) {
      values = arrayMap(values, baseUnary(iteratee));
    }
    if (comparator) {
      includes = arrayIncludesWith;
      isCommon = false;
    }
    else if (values.length >= LARGE_ARRAY_SIZE) {
      includes = cacheHas;
      isCommon = false;
      values = new SetCache(values);
    }
    outer:
    while (++index < length) {
      var value = array[index],
          computed = iteratee == null ? value : iteratee(value);

      value = (comparator || value !== 0) ? value : 0;
      if (isCommon && computed === computed) {
        var valuesIndex = valuesLength;
        while (valuesIndex--) {
          if (values[valuesIndex] === computed) {
            continue outer;
          }
        }
        result.push(value);
      }
      else if (!includes(values, computed, comparator)) {
        result.push(value);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.forEach` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array|Object} Returns `collection`.
   */
  var baseEach = createBaseEach(baseForOwn);

  /**
   * The base implementation of `_.forEachRight` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array|Object} Returns `collection`.
   */
  var baseEachRight = createBaseEach(baseForOwnRight, true);

  /**
   * The base implementation of `_.every` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {boolean} Returns `true` if all elements pass the predicate check,
   *  else `false`
   */
  function baseEvery(collection, predicate) {
    var result = true;
    baseEach(collection, function(value, index, collection) {
      result = !!predicate(value, index, collection);
      return result;
    });
    return result;
  }

  /**
   * The base implementation of methods like `_.max` and `_.min` which accepts a
   * `comparator` to determine the extremum value.
   *
   * @private
   * @param {Array} array The array to iterate over.
   * @param {Function} iteratee The iteratee invoked per iteration.
   * @param {Function} comparator The comparator used to compare values.
   * @returns {*} Returns the extremum value.
   */
  function baseExtremum(array, iteratee, comparator) {
    var index = -1,
        length = array.length;

    while (++index < length) {
      var value = array[index],
          current = iteratee(value);

      if (current != null && (computed === undefined
            ? (current === current && !isSymbol(current))
            : comparator(current, computed)
          )) {
        var computed = current,
            result = value;
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.fill` without an iteratee call guard.
   *
   * @private
   * @param {Array} array The array to fill.
   * @param {*} value The value to fill `array` with.
   * @param {number} [start=0] The start position.
   * @param {number} [end=array.length] The end position.
   * @returns {Array} Returns `array`.
   */
  function baseFill(array, value, start, end) {
    var length = array.length;

    start = toInteger(start);
    if (start < 0) {
      start = -start > length ? 0 : (length + start);
    }
    end = (end === undefined || end > length) ? length : toInteger(end);
    if (end < 0) {
      end += length;
    }
    end = start > end ? 0 : toLength(end);
    while (start < end) {
      array[start++] = value;
    }
    return array;
  }

  /**
   * The base implementation of `_.filter` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {Array} Returns the new filtered array.
   */
  function baseFilter(collection, predicate) {
    var result = [];
    baseEach(collection, function(value, index, collection) {
      if (predicate(value, index, collection)) {
        result.push(value);
      }
    });
    return result;
  }

  /**
   * The base implementation of `_.flatten` with support for restricting flattening.
   *
   * @private
   * @param {Array} array The array to flatten.
   * @param {number} depth The maximum recursion depth.
   * @param {boolean} [predicate=isFlattenable] The function invoked per iteration.
   * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks.
   * @param {Array} [result=[]] The initial result value.
   * @returns {Array} Returns the new flattened array.
   */
  function baseFlatten(array, depth, predicate, isStrict, result) {
    var index = -1,
        length = array.length;

    predicate || (predicate = isFlattenable);
    result || (result = []);

    while (++index < length) {
      var value = array[index];
      if (depth > 0 && predicate(value)) {
        if (depth > 1) {
          // Recursively flatten arrays (susceptible to call stack limits).
          baseFlatten(value, depth - 1, predicate, isStrict, result);
        } else {
          arrayPush(result, value);
        }
      } else if (!isStrict) {
        result[result.length] = value;
      }
    }
    return result;
  }

  /**
   * The base implementation of `baseForOwn` which iterates over `object`
   * properties returned by `keysFunc` and invokes `iteratee` for each property.
   * Iteratee functions may exit iteration early by explicitly returning `false`.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {Function} keysFunc The function to get the keys of `object`.
   * @returns {Object} Returns `object`.
   */
  var baseFor = createBaseFor();

  /**
   * This function is like `baseFor` except that it iterates over properties
   * in the opposite order.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {Function} keysFunc The function to get the keys of `object`.
   * @returns {Object} Returns `object`.
   */
  var baseForRight = createBaseFor(true);

  /**
   * The base implementation of `_.forOwn` without support for iteratee shorthands.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Object} Returns `object`.
   */
  function baseForOwn(object, iteratee) {
    return object && baseFor(object, iteratee, keys);
  }

  /**
   * The base implementation of `_.forOwnRight` without support for iteratee shorthands.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Object} Returns `object`.
   */
  function baseForOwnRight(object, iteratee) {
    return object && baseForRight(object, iteratee, keys);
  }

  /**
   * The base implementation of `_.functions` which creates an array of
   * `object` function property names filtered from `props`.
   *
   * @private
   * @param {Object} object The object to inspect.
   * @param {Array} props The property names to filter.
   * @returns {Array} Returns the function names.
   */
  function baseFunctions(object, props) {
    return arrayFilter(props, function(key) {
      return isFunction(object[key]);
    });
  }

  /**
   * The base implementation of `_.get` without support for default values.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the property to get.
   * @returns {*} Returns the resolved value.
   */
  function baseGet(object, path) {
    path = castPath(path, object);

    var index = 0,
        length = path.length;

    while (object != null && index < length) {
      object = object[toKey(path[index++])];
    }
    return (index && index == length) ? object : undefined;
  }

  /**
   * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
   * `keysFunc` and `symbolsFunc` to get the enumerable property names and
   * symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Function} keysFunc The function to get the keys of `object`.
   * @param {Function} symbolsFunc The function to get the symbols of `object`.
   * @returns {Array} Returns the array of property names and symbols.
   */
  function baseGetAllKeys(object, keysFunc, symbolsFunc) {
    var result = keysFunc(object);
    return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
  }

  /**
   * The base implementation of `getTag` without fallbacks for buggy environments.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the `toStringTag`.
   */
  function baseGetTag(value) {
    if (value == null) {
      return value === undefined ? undefinedTag : nullTag;
    }
    return (symToStringTag && symToStringTag in Object(value))
      ? getRawTag(value)
      : objectToString(value);
  }

  /**
   * The base implementation of `_.gt` which doesn't coerce arguments.
   *
   * @private
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is greater than `other`,
   *  else `false`.
   */
  function baseGt(value, other) {
    return value > other;
  }

  /**
   * The base implementation of `_.has` without support for deep paths.
   *
   * @private
   * @param {Object} [object] The object to query.
   * @param {Array|string} key The key to check.
   * @returns {boolean} Returns `true` if `key` exists, else `false`.
   */
  function baseHas(object, key) {
    return object != null && hasOwnProperty.call(object, key);
  }

  /**
   * The base implementation of `_.hasIn` without support for deep paths.
   *
   * @private
   * @param {Object} [object] The object to query.
   * @param {Array|string} key The key to check.
   * @returns {boolean} Returns `true` if `key` exists, else `false`.
   */
  function baseHasIn(object, key) {
    return object != null && key in Object(object);
  }

  /**
   * The base implementation of `_.inRange` which doesn't coerce arguments.
   *
   * @private
   * @param {number} number The number to check.
   * @param {number} start The start of the range.
   * @param {number} end The end of the range.
   * @returns {boolean} Returns `true` if `number` is in the range, else `false`.
   */
  function baseInRange(number, start, end) {
    return number >= nativeMin(start, end) && number < nativeMax(start, end);
  }

  /**
   * The base implementation of methods like `_.intersection`, without support
   * for iteratee shorthands, that accepts an array of arrays to inspect.
   *
   * @private
   * @param {Array} arrays The arrays to inspect.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of shared values.
   */
  function baseIntersection(arrays, iteratee, comparator) {
    var includes = comparator ? arrayIncludesWith : arrayIncludes,
        length = arrays[0].length,
        othLength = arrays.length,
        othIndex = othLength,
        caches = Array(othLength),
        maxLength = Infinity,
        result = [];

    while (othIndex--) {
      var array = arrays[othIndex];
      if (othIndex && iteratee) {
        array = arrayMap(array, baseUnary(iteratee));
      }
      maxLength = nativeMin(array.length, maxLength);
      caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120))
        ? new SetCache(othIndex && array)
        : undefined;
    }
    array = arrays[0];

    var index = -1,
        seen = caches[0];

    outer:
    while (++index < length && result.length < maxLength) {
      var value = array[index],
          computed = iteratee ? iteratee(value) : value;

      value = (comparator || value !== 0) ? value : 0;
      if (!(seen
            ? cacheHas(seen, computed)
            : includes(result, computed, comparator)
          )) {
        othIndex = othLength;
        while (--othIndex) {
          var cache = caches[othIndex];
          if (!(cache
                ? cacheHas(cache, computed)
                : includes(arrays[othIndex], computed, comparator))
              ) {
            continue outer;
          }
        }
        if (seen) {
          seen.push(computed);
        }
        result.push(value);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.invert` and `_.invertBy` which inverts
   * `object` with values transformed by `iteratee` and set by `setter`.
   *
   * @private
   * @param {Object} object The object to iterate over.
   * @param {Function} setter The function to set `accumulator` values.
   * @param {Function} iteratee The iteratee to transform values.
   * @param {Object} accumulator The initial inverted object.
   * @returns {Function} Returns `accumulator`.
   */
  function baseInverter(object, setter, iteratee, accumulator) {
    baseForOwn(object, function(value, key, object) {
      setter(accumulator, iteratee(value), key, object);
    });
    return accumulator;
  }

  /**
   * The base implementation of `_.invoke` without support for individual
   * method arguments.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the method to invoke.
   * @param {Array} args The arguments to invoke the method with.
   * @returns {*} Returns the result of the invoked method.
   */
  function baseInvoke(object, path, args) {
    path = castPath(path, object);
    object = parent(object, path);
    var func = object == null ? object : object[toKey(last(path))];
    return func == null ? undefined : apply(func, object, args);
  }

  /**
   * The base implementation of `_.isArguments`.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an `arguments` object,
   */
  function baseIsArguments(value) {
    return isObjectLike(value) && baseGetTag(value) == argsTag;
  }

  /**
   * The base implementation of `_.isArrayBuffer` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.
   */
  function baseIsArrayBuffer(value) {
    return isObjectLike(value) && baseGetTag(value) == arrayBufferTag;
  }

  /**
   * The base implementation of `_.isDate` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a date object, else `false`.
   */
  function baseIsDate(value) {
    return isObjectLike(value) && baseGetTag(value) == dateTag;
  }

  /**
   * The base implementation of `_.isEqual` which supports partial comparisons
   * and tracks traversed objects.
   *
   * @private
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @param {boolean} bitmask The bitmask flags.
   *  1 - Unordered comparison
   *  2 - Partial comparison
   * @param {Function} [customizer] The function to customize comparisons.
   * @param {Object} [stack] Tracks traversed `value` and `other` objects.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   */
  function baseIsEqual(value, other, bitmask, customizer, stack) {
    if (value === other) {
      return true;
    }
    if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) {
      return value !== value && other !== other;
    }
    return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack);
  }

  /**
   * A specialized version of `baseIsEqual` for arrays and objects which performs
   * deep comparisons and tracks traversed objects enabling objects with circular
   * references to be compared.
   *
   * @private
   * @param {Object} object The object to compare.
   * @param {Object} other The other object to compare.
   * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
   * @param {Function} customizer The function to customize comparisons.
   * @param {Function} equalFunc The function to determine equivalents of values.
   * @param {Object} [stack] Tracks traversed `object` and `other` objects.
   * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
   */
  function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
    var objIsArr = isArray(object),
        othIsArr = isArray(other),
        objTag = objIsArr ? arrayTag : getTag(object),
        othTag = othIsArr ? arrayTag : getTag(other);

    objTag = objTag == argsTag ? objectTag : objTag;
    othTag = othTag == argsTag ? objectTag : othTag;

    var objIsObj = objTag == objectTag,
        othIsObj = othTag == objectTag,
        isSameTag = objTag == othTag;

    if (isSameTag && isBuffer(object)) {
      if (!isBuffer(other)) {
        return false;
      }
      objIsArr = true;
      objIsObj = false;
    }
    if (isSameTag && !objIsObj) {
      stack || (stack = new Stack);
      return (objIsArr || isTypedArray(object))
        ? equalArrays(object, other, bitmask, customizer, equalFunc, stack)
        : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack);
    }
    if (!(bitmask & COMPARE_PARTIAL_FLAG)) {
      var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
          othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');

      if (objIsWrapped || othIsWrapped) {
        var objUnwrapped = objIsWrapped ? object.value() : object,
            othUnwrapped = othIsWrapped ? other.value() : other;

        stack || (stack = new Stack);
        return equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack);
      }
    }
    if (!isSameTag) {
      return false;
    }
    stack || (stack = new Stack);
    return equalObjects(object, other, bitmask, customizer, equalFunc, stack);
  }

  /**
   * The base implementation of `_.isMap` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a map, else `false`.
   */
  function baseIsMap(value) {
    return isObjectLike(value) && getTag(value) == mapTag;
  }

  /**
   * The base implementation of `_.isMatch` without support for iteratee shorthands.
   *
   * @private
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property values to match.
   * @param {Array} matchData The property names, values, and compare flags to match.
   * @param {Function} [customizer] The function to customize comparisons.
   * @returns {boolean} Returns `true` if `object` is a match, else `false`.
   */
  function baseIsMatch(object, source, matchData, customizer) {
    var index = matchData.length,
        length = index,
        noCustomizer = !customizer;

    if (object == null) {
      return !length;
    }
    object = Object(object);
    while (index--) {
      var data = matchData[index];
      if ((noCustomizer && data[2])
            ? data[1] !== object[data[0]]
            : !(data[0] in object)
          ) {
        return false;
      }
    }
    while (++index < length) {
      data = matchData[index];
      var key = data[0],
          objValue = object[key],
          srcValue = data[1];

      if (noCustomizer && data[2]) {
        if (objValue === undefined && !(key in object)) {
          return false;
        }
      } else {
        var stack = new Stack;
        if (customizer) {
          var result = customizer(objValue, srcValue, key, object, source, stack);
        }
        if (!(result === undefined
              ? baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG, customizer, stack)
              : result
            )) {
          return false;
        }
      }
    }
    return true;
  }

  /**
   * The base implementation of `_.isNative` without bad shim checks.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a native function,
   *  else `false`.
   */
  function baseIsNative(value) {
    if (!isObject(value) || isMasked(value)) {
      return false;
    }
    var pattern = isFunction(value) ? reIsNative : reIsHostCtor;
    return pattern.test(toSource(value));
  }

  /**
   * The base implementation of `_.isRegExp` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
   */
  function baseIsRegExp(value) {
    return isObjectLike(value) && baseGetTag(value) == regexpTag;
  }

  /**
   * The base implementation of `_.isSet` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a set, else `false`.
   */
  function baseIsSet(value) {
    return isObjectLike(value) && getTag(value) == setTag;
  }

  /**
   * The base implementation of `_.isTypedArray` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
   */
  function baseIsTypedArray(value) {
    return isObjectLike(value) &&
      isLength(value.length) && !!typedArrayTags[baseGetTag(value)];
  }

  /**
   * The base implementation of `_.iteratee`.
   *
   * @private
   * @param {*} [value=_.identity] The value to convert to an iteratee.
   * @returns {Function} Returns the iteratee.
   */
  function baseIteratee(value) {
    // Don't store the `typeof` result in a variable to avoid a JIT bug in Safari 9.
    // See https://bugs.webkit.org/show_bug.cgi?id=156034 for more details.
    if (typeof value == 'function') {
      return value;
    }
    if (value == null) {
      return identity;
    }
    if (typeof value == 'object') {
      return isArray(value)
        ? baseMatchesProperty(value[0], value[1])
        : baseMatches(value);
    }
    return property(value);
  }

  /**
   * The base implementation of `_.keys` which doesn't treat sparse arrays as dense.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function baseKeys(object) {
    if (!isPrototype(object)) {
      return nativeKeys(object);
    }
    var result = [];
    for (var key in Object(object)) {
      if (hasOwnProperty.call(object, key) && key != 'constructor') {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function baseKeysIn(object) {
    if (!isObject(object)) {
      return nativeKeysIn(object);
    }
    var isProto = isPrototype(object),
        result = [];

    for (var key in object) {
      if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.lt` which doesn't coerce arguments.
   *
   * @private
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is less than `other`,
   *  else `false`.
   */
  function baseLt(value, other) {
    return value < other;
  }

  /**
   * The base implementation of `_.map` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns the new mapped array.
   */
  function baseMap(collection, iteratee) {
    var index = -1,
        result = isArrayLike(collection) ? Array(collection.length) : [];

    baseEach(collection, function(value, key, collection) {
      result[++index] = iteratee(value, key, collection);
    });
    return result;
  }

  /**
   * The base implementation of `_.matches` which doesn't clone `source`.
   *
   * @private
   * @param {Object} source The object of property values to match.
   * @returns {Function} Returns the new spec function.
   */
  function baseMatches(source) {
    var matchData = getMatchData(source);
    if (matchData.length == 1 && matchData[0][2]) {
      return matchesStrictComparable(matchData[0][0], matchData[0][1]);
    }
    return function(object) {
      return object === source || baseIsMatch(object, source, matchData);
    };
  }

  /**
   * The base implementation of `_.matchesProperty` which doesn't clone `srcValue`.
   *
   * @private
   * @param {string} path The path of the property to get.
   * @param {*} srcValue The value to match.
   * @returns {Function} Returns the new spec function.
   */
  function baseMatchesProperty(path, srcValue) {
    if (isKey(path) && isStrictComparable(srcValue)) {
      return matchesStrictComparable(toKey(path), srcValue);
    }
    return function(object) {
      var objValue = get(object, path);
      return (objValue === undefined && objValue === srcValue)
        ? hasIn(object, path)
        : baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG);
    };
  }

  /**
   * The base implementation of `_.merge` without support for multiple sources.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @param {number} srcIndex The index of `source`.
   * @param {Function} [customizer] The function to customize merged values.
   * @param {Object} [stack] Tracks traversed source values and their merged
   *  counterparts.
   */
  function baseMerge(object, source, srcIndex, customizer, stack) {
    if (object === source) {
      return;
    }
    baseFor(source, function(srcValue, key) {
      stack || (stack = new Stack);
      if (isObject(srcValue)) {
        baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack);
      }
      else {
        var newValue = customizer
          ? customizer(safeGet(object, key), srcValue, (key + ''), object, source, stack)
          : undefined;

        if (newValue === undefined) {
          newValue = srcValue;
        }
        assignMergeValue(object, key, newValue);
      }
    }, keysIn);
  }

  /**
   * A specialized version of `baseMerge` for arrays and objects which performs
   * deep merges and tracks traversed objects enabling objects with circular
   * references to be merged.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @param {string} key The key of the value to merge.
   * @param {number} srcIndex The index of `source`.
   * @param {Function} mergeFunc The function to merge values.
   * @param {Function} [customizer] The function to customize assigned values.
   * @param {Object} [stack] Tracks traversed source values and their merged
   *  counterparts.
   */
  function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) {
    var objValue = safeGet(object, key),
        srcValue = safeGet(source, key),
        stacked = stack.get(srcValue);

    if (stacked) {
      assignMergeValue(object, key, stacked);
      return;
    }
    var newValue = customizer
      ? customizer(objValue, srcValue, (key + ''), object, source, stack)
      : undefined;

    var isCommon = newValue === undefined;

    if (isCommon) {
      var isArr = isArray(srcValue),
          isBuff = !isArr && isBuffer(srcValue),
          isTyped = !isArr && !isBuff && isTypedArray(srcValue);

      newValue = srcValue;
      if (isArr || isBuff || isTyped) {
        if (isArray(objValue)) {
          newValue = objValue;
        }
        else if (isArrayLikeObject(objValue)) {
          newValue = copyArray(objValue);
        }
        else if (isBuff) {
          isCommon = false;
          newValue = cloneBuffer(srcValue, true);
        }
        else if (isTyped) {
          isCommon = false;
          newValue = cloneTypedArray(srcValue, true);
        }
        else {
          newValue = [];
        }
      }
      else if (isPlainObject(srcValue) || isArguments(srcValue)) {
        newValue = objValue;
        if (isArguments(objValue)) {
          newValue = toPlainObject(objValue);
        }
        else if (!isObject(objValue) || isFunction(objValue)) {
          newValue = initCloneObject(srcValue);
        }
      }
      else {
        isCommon = false;
      }
    }
    if (isCommon) {
      // Recursively merge objects and arrays (susceptible to call stack limits).
      stack.set(srcValue, newValue);
      mergeFunc(newValue, srcValue, srcIndex, customizer, stack);
      stack['delete'](srcValue);
    }
    assignMergeValue(object, key, newValue);
  }

  /**
   * The base implementation of `_.nth` which doesn't coerce arguments.
   *
   * @private
   * @param {Array} array The array to query.
   * @param {number} n The index of the element to return.
   * @returns {*} Returns the nth element of `array`.
   */
  function baseNth(array, n) {
    var length = array.length;
    if (!length) {
      return;
    }
    n += n < 0 ? length : 0;
    return isIndex(n, length) ? array[n] : undefined;
  }

  /**
   * The base implementation of `_.orderBy` without param guards.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by.
   * @param {string[]} orders The sort orders of `iteratees`.
   * @returns {Array} Returns the new sorted array.
   */
  function baseOrderBy(collection, iteratees, orders) {
    var index = -1;
    iteratees = arrayMap(iteratees.length ? iteratees : [identity], baseUnary(getIteratee()));

    var result = baseMap(collection, function(value, key, collection) {
      var criteria = arrayMap(iteratees, function(iteratee) {
        return iteratee(value);
      });
      return { 'criteria': criteria, 'index': ++index, 'value': value };
    });

    return baseSortBy(result, function(object, other) {
      return compareMultiple(object, other, orders);
    });
  }

  /**
   * The base implementation of `_.pick` without support for individual
   * property identifiers.
   *
   * @private
   * @param {Object} object The source object.
   * @param {string[]} paths The property paths to pick.
   * @returns {Object} Returns the new object.
   */
  function basePick(object, paths) {
    return basePickBy(object, paths, function(value, path) {
      return hasIn(object, path);
    });
  }

  /**
   * The base implementation of  `_.pickBy` without support for iteratee shorthands.
   *
   * @private
   * @param {Object} object The source object.
   * @param {string[]} paths The property paths to pick.
   * @param {Function} predicate The function invoked per property.
   * @returns {Object} Returns the new object.
   */
  function basePickBy(object, paths, predicate) {
    var index = -1,
        length = paths.length,
        result = {};

    while (++index < length) {
      var path = paths[index],
          value = baseGet(object, path);

      if (predicate(value, path)) {
        baseSet(result, castPath(path, object), value);
      }
    }
    return result;
  }

  /**
   * A specialized version of `baseProperty` which supports deep paths.
   *
   * @private
   * @param {Array|string} path The path of the property to get.
   * @returns {Function} Returns the new accessor function.
   */
  function basePropertyDeep(path) {
    return function(object) {
      return baseGet(object, path);
    };
  }

  /**
   * The base implementation of `_.pullAllBy` without support for iteratee
   * shorthands.
   *
   * @private
   * @param {Array} array The array to modify.
   * @param {Array} values The values to remove.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns `array`.
   */
  function basePullAll(array, values, iteratee, comparator) {
    var indexOf = comparator ? baseIndexOfWith : baseIndexOf,
        index = -1,
        length = values.length,
        seen = array;

    if (array === values) {
      values = copyArray(values);
    }
    if (iteratee) {
      seen = arrayMap(array, baseUnary(iteratee));
    }
    while (++index < length) {
      var fromIndex = 0,
          value = values[index],
          computed = iteratee ? iteratee(value) : value;

      while ((fromIndex = indexOf(seen, computed, fromIndex, comparator)) > -1) {
        if (seen !== array) {
          splice.call(seen, fromIndex, 1);
        }
        splice.call(array, fromIndex, 1);
      }
    }
    return array;
  }

  /**
   * The base implementation of `_.pullAt` without support for individual
   * indexes or capturing the removed elements.
   *
   * @private
   * @param {Array} array The array to modify.
   * @param {number[]} indexes The indexes of elements to remove.
   * @returns {Array} Returns `array`.
   */
  function basePullAt(array, indexes) {
    var length = array ? indexes.length : 0,
        lastIndex = length - 1;

    while (length--) {
      var index = indexes[length];
      if (length == lastIndex || index !== previous) {
        var previous = index;
        if (isIndex(index)) {
          splice.call(array, index, 1);
        } else {
          baseUnset(array, index);
        }
      }
    }
    return array;
  }

  /**
   * The base implementation of `_.random` without support for returning
   * floating-point numbers.
   *
   * @private
   * @param {number} lower The lower bound.
   * @param {number} upper The upper bound.
   * @returns {number} Returns the random number.
   */
  function baseRandom(lower, upper) {
    return lower + nativeFloor(nativeRandom() * (upper - lower + 1));
  }

  /**
   * The base implementation of `_.range` and `_.rangeRight` which doesn't
   * coerce arguments.
   *
   * @private
   * @param {number} start The start of the range.
   * @param {number} end The end of the range.
   * @param {number} step The value to increment or decrement by.
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Array} Returns the range of numbers.
   */
  function baseRange(start, end, step, fromRight) {
    var index = -1,
        length = nativeMax(nativeCeil((end - start) / (step || 1)), 0),
        result = Array(length);

    while (length--) {
      result[fromRight ? length : ++index] = start;
      start += step;
    }
    return result;
  }

  /**
   * The base implementation of `_.repeat` which doesn't coerce arguments.
   *
   * @private
   * @param {string} string The string to repeat.
   * @param {number} n The number of times to repeat the string.
   * @returns {string} Returns the repeated string.
   */
  function baseRepeat(string, n) {
    var result = '';
    if (!string || n < 1 || n > MAX_SAFE_INTEGER) {
      return result;
    }
    // Leverage the exponentiation by squaring algorithm for a faster repeat.
    // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details.
    do {
      if (n % 2) {
        result += string;
      }
      n = nativeFloor(n / 2);
      if (n) {
        string += string;
      }
    } while (n);

    return result;
  }

  /**
   * The base implementation of `_.rest` which doesn't validate or coerce arguments.
   *
   * @private
   * @param {Function} func The function to apply a rest parameter to.
   * @param {number} [start=func.length-1] The start position of the rest parameter.
   * @returns {Function} Returns the new function.
   */
  function baseRest(func, start) {
    return setToString(overRest(func, start, identity), func + '');
  }

  /**
   * The base implementation of `_.sample`.
   *
   * @private
   * @param {Array|Object} collection The collection to sample.
   * @returns {*} Returns the random element.
   */
  function baseSample(collection) {
    return arraySample(values(collection));
  }

  /**
   * The base implementation of `_.sampleSize` without param guards.
   *
   * @private
   * @param {Array|Object} collection The collection to sample.
   * @param {number} n The number of elements to sample.
   * @returns {Array} Returns the random elements.
   */
  function baseSampleSize(collection, n) {
    var array = values(collection);
    return shuffleSelf(array, baseClamp(n, 0, array.length));
  }

  /**
   * The base implementation of `_.set`.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to set.
   * @param {*} value The value to set.
   * @param {Function} [customizer] The function to customize path creation.
   * @returns {Object} Returns `object`.
   */
  function baseSet(object, path, value, customizer) {
    if (!isObject(object)) {
      return object;
    }
    path = castPath(path, object);

    var index = -1,
        length = path.length,
        lastIndex = length - 1,
        nested = object;

    while (nested != null && ++index < length) {
      var key = toKey(path[index]),
          newValue = value;

      if (index != lastIndex) {
        var objValue = nested[key];
        newValue = customizer ? customizer(objValue, key, nested) : undefined;
        if (newValue === undefined) {
          newValue = isObject(objValue)
            ? objValue
            : (isIndex(path[index + 1]) ? [] : {});
        }
      }
      assignValue(nested, key, newValue);
      nested = nested[key];
    }
    return object;
  }

  /**
   * The base implementation of `setData` without support for hot loop shorting.
   *
   * @private
   * @param {Function} func The function to associate metadata with.
   * @param {*} data The metadata.
   * @returns {Function} Returns `func`.
   */
  var baseSetData = !metaMap ? identity : function(func, data) {
    metaMap.set(func, data);
    return func;
  };

  /**
   * The base implementation of `setToString` without support for hot loop shorting.
   *
   * @private
   * @param {Function} func The function to modify.
   * @param {Function} string The `toString` result.
   * @returns {Function} Returns `func`.
   */
  var baseSetToString = !defineProperty ? identity : function(func, string) {
    return defineProperty(func, 'toString', {
      'configurable': true,
      'enumerable': false,
      'value': constant(string),
      'writable': true
    });
  };

  /**
   * The base implementation of `_.shuffle`.
   *
   * @private
   * @param {Array|Object} collection The collection to shuffle.
   * @returns {Array} Returns the new shuffled array.
   */
  function baseShuffle(collection) {
    return shuffleSelf(values(collection));
  }

  /**
   * The base implementation of `_.slice` without an iteratee call guard.
   *
   * @private
   * @param {Array} array The array to slice.
   * @param {number} [start=0] The start position.
   * @param {number} [end=array.length] The end position.
   * @returns {Array} Returns the slice of `array`.
   */
  function baseSlice(array, start, end) {
    var index = -1,
        length = array.length;

    if (start < 0) {
      start = -start > length ? 0 : (length + start);
    }
    end = end > length ? length : end;
    if (end < 0) {
      end += length;
    }
    length = start > end ? 0 : ((end - start) >>> 0);
    start >>>= 0;

    var result = Array(length);
    while (++index < length) {
      result[index] = array[index + start];
    }
    return result;
  }

  /**
   * The base implementation of `_.some` without support for iteratee shorthands.
   *
   * @private
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {boolean} Returns `true` if any element passes the predicate check,
   *  else `false`.
   */
  function baseSome(collection, predicate) {
    var result;

    baseEach(collection, function(value, index, collection) {
      result = predicate(value, index, collection);
      return !result;
    });
    return !!result;
  }

  /**
   * The base implementation of `_.sortedIndex` and `_.sortedLastIndex` which
   * performs a binary search of `array` to determine the index at which `value`
   * should be inserted into `array` in order to maintain its sort order.
   *
   * @private
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @param {boolean} [retHighest] Specify returning the highest qualified index.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   */
  function baseSortedIndex(array, value, retHighest) {
    var low = 0,
        high = array == null ? low : array.length;

    if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) {
      while (low < high) {
        var mid = (low + high) >>> 1,
            computed = array[mid];

        if (computed !== null && !isSymbol(computed) &&
            (retHighest ? (computed <= value) : (computed < value))) {
          low = mid + 1;
        } else {
          high = mid;
        }
      }
      return high;
    }
    return baseSortedIndexBy(array, value, identity, retHighest);
  }

  /**
   * The base implementation of `_.sortedIndexBy` and `_.sortedLastIndexBy`
   * which invokes `iteratee` for `value` and each element of `array` to compute
   * their sort ranking. The iteratee is invoked with one argument; (value).
   *
   * @private
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @param {Function} iteratee The iteratee invoked per element.
   * @param {boolean} [retHighest] Specify returning the highest qualified index.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   */
  function baseSortedIndexBy(array, value, iteratee, retHighest) {
    value = iteratee(value);

    var low = 0,
        high = array == null ? 0 : array.length,
        valIsNaN = value !== value,
        valIsNull = value === null,
        valIsSymbol = isSymbol(value),
        valIsUndefined = value === undefined;

    while (low < high) {
      var mid = nativeFloor((low + high) / 2),
          computed = iteratee(array[mid]),
          othIsDefined = computed !== undefined,
          othIsNull = computed === null,
          othIsReflexive = computed === computed,
          othIsSymbol = isSymbol(computed);

      if (valIsNaN) {
        var setLow = retHighest || othIsReflexive;
      } else if (valIsUndefined) {
        setLow = othIsReflexive && (retHighest || othIsDefined);
      } else if (valIsNull) {
        setLow = othIsReflexive && othIsDefined && (retHighest || !othIsNull);
      } else if (valIsSymbol) {
        setLow = othIsReflexive && othIsDefined && !othIsNull && (retHighest || !othIsSymbol);
      } else if (othIsNull || othIsSymbol) {
        setLow = false;
      } else {
        setLow = retHighest ? (computed <= value) : (computed < value);
      }
      if (setLow) {
        low = mid + 1;
      } else {
        high = mid;
      }
    }
    return nativeMin(high, MAX_ARRAY_INDEX);
  }

  /**
   * The base implementation of `_.sortedUniq` and `_.sortedUniqBy` without
   * support for iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @returns {Array} Returns the new duplicate free array.
   */
  function baseSortedUniq(array, iteratee) {
    var index = -1,
        length = array.length,
        resIndex = 0,
        result = [];

    while (++index < length) {
      var value = array[index],
          computed = iteratee ? iteratee(value) : value;

      if (!index || !eq(computed, seen)) {
        var seen = computed;
        result[resIndex++] = value === 0 ? 0 : value;
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.toNumber` which doesn't ensure correct
   * conversions of binary, hexadecimal, or octal string values.
   *
   * @private
   * @param {*} value The value to process.
   * @returns {number} Returns the number.
   */
  function baseToNumber(value) {
    if (typeof value == 'number') {
      return value;
    }
    if (isSymbol(value)) {
      return NAN;
    }
    return +value;
  }

  /**
   * The base implementation of `_.toString` which doesn't convert nullish
   * values to empty strings.
   *
   * @private
   * @param {*} value The value to process.
   * @returns {string} Returns the string.
   */
  function baseToString(value) {
    // Exit early for strings to avoid a performance hit in some environments.
    if (typeof value == 'string') {
      return value;
    }
    if (isArray(value)) {
      // Recursively convert values (susceptible to call stack limits).
      return arrayMap(value, baseToString) + '';
    }
    if (isSymbol(value)) {
      return symbolToString ? symbolToString.call(value) : '';
    }
    var result = (value + '');
    return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
  }

  /**
   * The base implementation of `_.uniqBy` without support for iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new duplicate free array.
   */
  function baseUniq(array, iteratee, comparator) {
    var index = -1,
        includes = arrayIncludes,
        length = array.length,
        isCommon = true,
        result = [],
        seen = result;

    if (comparator) {
      isCommon = false;
      includes = arrayIncludesWith;
    }
    else if (length >= LARGE_ARRAY_SIZE) {
      var set = iteratee ? null : createSet(array);
      if (set) {
        return setToArray(set);
      }
      isCommon = false;
      includes = cacheHas;
      seen = new SetCache;
    }
    else {
      seen = iteratee ? [] : result;
    }
    outer:
    while (++index < length) {
      var value = array[index],
          computed = iteratee ? iteratee(value) : value;

      value = (comparator || value !== 0) ? value : 0;
      if (isCommon && computed === computed) {
        var seenIndex = seen.length;
        while (seenIndex--) {
          if (seen[seenIndex] === computed) {
            continue outer;
          }
        }
        if (iteratee) {
          seen.push(computed);
        }
        result.push(value);
      }
      else if (!includes(seen, computed, comparator)) {
        if (seen !== result) {
          seen.push(computed);
        }
        result.push(value);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.unset`.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {Array|string} path The property path to unset.
   * @returns {boolean} Returns `true` if the property is deleted, else `false`.
   */
  function baseUnset(object, path) {
    path = castPath(path, object);
    object = parent(object, path);
    return object == null || delete object[toKey(last(path))];
  }

  /**
   * The base implementation of `_.update`.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to update.
   * @param {Function} updater The function to produce the updated value.
   * @param {Function} [customizer] The function to customize path creation.
   * @returns {Object} Returns `object`.
   */
  function baseUpdate(object, path, updater, customizer) {
    return baseSet(object, path, updater(baseGet(object, path)), customizer);
  }

  /**
   * The base implementation of methods like `_.dropWhile` and `_.takeWhile`
   * without support for iteratee shorthands.
   *
   * @private
   * @param {Array} array The array to query.
   * @param {Function} predicate The function invoked per iteration.
   * @param {boolean} [isDrop] Specify dropping elements instead of taking them.
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Array} Returns the slice of `array`.
   */
  function baseWhile(array, predicate, isDrop, fromRight) {
    var length = array.length,
        index = fromRight ? length : -1;

    while ((fromRight ? index-- : ++index < length) &&
      predicate(array[index], index, array)) {}

    return isDrop
      ? baseSlice(array, (fromRight ? 0 : index), (fromRight ? index + 1 : length))
      : baseSlice(array, (fromRight ? index + 1 : 0), (fromRight ? length : index));
  }

  /**
   * The base implementation of `wrapperValue` which returns the result of
   * performing a sequence of actions on the unwrapped `value`, where each
   * successive action is supplied the return value of the previous.
   *
   * @private
   * @param {*} value The unwrapped value.
   * @param {Array} actions Actions to perform to resolve the unwrapped value.
   * @returns {*} Returns the resolved value.
   */
  function baseWrapperValue(value, actions) {
    var result = value;
    if (result instanceof LazyWrapper) {
      result = result.value();
    }
    return arrayReduce(actions, function(result, action) {
      return action.func.apply(action.thisArg, arrayPush([result], action.args));
    }, result);
  }

  /**
   * The base implementation of methods like `_.xor`, without support for
   * iteratee shorthands, that accepts an array of arrays to inspect.
   *
   * @private
   * @param {Array} arrays The arrays to inspect.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of values.
   */
  function baseXor(arrays, iteratee, comparator) {
    var length = arrays.length;
    if (length < 2) {
      return length ? baseUniq(arrays[0]) : [];
    }
    var index = -1,
        result = Array(length);

    while (++index < length) {
      var array = arrays[index],
          othIndex = -1;

      while (++othIndex < length) {
        if (othIndex != index) {
          result[index] = baseDifference(result[index] || array, arrays[othIndex], iteratee, comparator);
        }
      }
    }
    return baseUniq(baseFlatten(result, 1), iteratee, comparator);
  }

  /**
   * This base implementation of `_.zipObject` which assigns values using `assignFunc`.
   *
   * @private
   * @param {Array} props The property identifiers.
   * @param {Array} values The property values.
   * @param {Function} assignFunc The function to assign values.
   * @returns {Object} Returns the new object.
   */
  function baseZipObject(props, values, assignFunc) {
    var index = -1,
        length = props.length,
        valsLength = values.length,
        result = {};

    while (++index < length) {
      var value = index < valsLength ? values[index] : undefined;
      assignFunc(result, props[index], value);
    }
    return result;
  }

  /**
   * Casts `value` to an empty array if it's not an array like object.
   *
   * @private
   * @param {*} value The value to inspect.
   * @returns {Array|Object} Returns the cast array-like object.
   */
  function castArrayLikeObject(value) {
    return isArrayLikeObject(value) ? value : [];
  }

  /**
   * Casts `value` to `identity` if it's not a function.
   *
   * @private
   * @param {*} value The value to inspect.
   * @returns {Function} Returns cast function.
   */
  function castFunction(value) {
    return typeof value == 'function' ? value : identity;
  }

  /**
   * Casts `value` to a path array if it's not one.
   *
   * @private
   * @param {*} value The value to inspect.
   * @param {Object} [object] The object to query keys on.
   * @returns {Array} Returns the cast property path array.
   */
  function castPath(value, object) {
    if (isArray(value)) {
      return value;
    }
    return isKey(value, object) ? [value] : stringToPath(toString(value));
  }

  /**
   * A `baseRest` alias which can be replaced with `identity` by module
   * replacement plugins.
   *
   * @private
   * @type {Function}
   * @param {Function} func The function to apply a rest parameter to.
   * @returns {Function} Returns the new function.
   */
  var castRest = baseRest;

  /**
   * Casts `array` to a slice if it's needed.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {number} start The start position.
   * @param {number} [end=array.length] The end position.
   * @returns {Array} Returns the cast slice.
   */
  function castSlice(array, start, end) {
    var length = array.length;
    end = end === undefined ? length : end;
    return (!start && end >= length) ? array : baseSlice(array, start, end);
  }

  /**
   * A simple wrapper around the global [`clearTimeout`](https://mdn.io/clearTimeout).
   *
   * @private
   * @param {number|Object} id The timer id or timeout object of the timer to clear.
   */
  var clearTimeout = ctxClearTimeout || function(id) {
    return root.clearTimeout(id);
  };

  /**
   * Creates a clone of  `buffer`.
   *
   * @private
   * @param {Buffer} buffer The buffer to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Buffer} Returns the cloned buffer.
   */
  function cloneBuffer(buffer, isDeep) {
    if (isDeep) {
      return buffer.slice();
    }
    var length = buffer.length,
        result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(length);

    buffer.copy(result);
    return result;
  }

  /**
   * Creates a clone of `arrayBuffer`.
   *
   * @private
   * @param {ArrayBuffer} arrayBuffer The array buffer to clone.
   * @returns {ArrayBuffer} Returns the cloned array buffer.
   */
  function cloneArrayBuffer(arrayBuffer) {
    var result = new arrayBuffer.constructor(arrayBuffer.byteLength);
    new Uint8Array(result).set(new Uint8Array(arrayBuffer));
    return result;
  }

  /**
   * Creates a clone of `dataView`.
   *
   * @private
   * @param {Object} dataView The data view to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned data view.
   */
  function cloneDataView(dataView, isDeep) {
    var buffer = isDeep ? cloneArrayBuffer(dataView.buffer) : dataView.buffer;
    return new dataView.constructor(buffer, dataView.byteOffset, dataView.byteLength);
  }

  /**
   * Creates a clone of `regexp`.
   *
   * @private
   * @param {Object} regexp The regexp to clone.
   * @returns {Object} Returns the cloned regexp.
   */
  function cloneRegExp(regexp) {
    var result = new regexp.constructor(regexp.source, reFlags.exec(regexp));
    result.lastIndex = regexp.lastIndex;
    return result;
  }

  /**
   * Creates a clone of the `symbol` object.
   *
   * @private
   * @param {Object} symbol The symbol object to clone.
   * @returns {Object} Returns the cloned symbol object.
   */
  function cloneSymbol(symbol) {
    return symbolValueOf ? Object(symbolValueOf.call(symbol)) : {};
  }

  /**
   * Creates a clone of `typedArray`.
   *
   * @private
   * @param {Object} typedArray The typed array to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned typed array.
   */
  function cloneTypedArray(typedArray, isDeep) {
    var buffer = isDeep ? cloneArrayBuffer(typedArray.buffer) : typedArray.buffer;
    return new typedArray.constructor(buffer, typedArray.byteOffset, typedArray.length);
  }

  /**
   * Compares values to sort them in ascending order.
   *
   * @private
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {number} Returns the sort order indicator for `value`.
   */
  function compareAscending(value, other) {
    if (value !== other) {
      var valIsDefined = value !== undefined,
          valIsNull = value === null,
          valIsReflexive = value === value,
          valIsSymbol = isSymbol(value);

      var othIsDefined = other !== undefined,
          othIsNull = other === null,
          othIsReflexive = other === other,
          othIsSymbol = isSymbol(other);

      if ((!othIsNull && !othIsSymbol && !valIsSymbol && value > other) ||
          (valIsSymbol && othIsDefined && othIsReflexive && !othIsNull && !othIsSymbol) ||
          (valIsNull && othIsDefined && othIsReflexive) ||
          (!valIsDefined && othIsReflexive) ||
          !valIsReflexive) {
        return 1;
      }
      if ((!valIsNull && !valIsSymbol && !othIsSymbol && value < other) ||
          (othIsSymbol && valIsDefined && valIsReflexive && !valIsNull && !valIsSymbol) ||
          (othIsNull && valIsDefined && valIsReflexive) ||
          (!othIsDefined && valIsReflexive) ||
          !othIsReflexive) {
        return -1;
      }
    }
    return 0;
  }

  /**
   * Used by `_.orderBy` to compare multiple properties of a value to another
   * and stable sort them.
   *
   * If `orders` is unspecified, all values are sorted in ascending order. Otherwise,
   * specify an order of "desc" for descending or "asc" for ascending sort order
   * of corresponding values.
   *
   * @private
   * @param {Object} object The object to compare.
   * @param {Object} other The other object to compare.
   * @param {boolean[]|string[]} orders The order to sort by for each property.
   * @returns {number} Returns the sort order indicator for `object`.
   */
  function compareMultiple(object, other, orders) {
    var index = -1,
        objCriteria = object.criteria,
        othCriteria = other.criteria,
        length = objCriteria.length,
        ordersLength = orders.length;

    while (++index < length) {
      var result = compareAscending(objCriteria[index], othCriteria[index]);
      if (result) {
        if (index >= ordersLength) {
          return result;
        }
        var order = orders[index];
        return result * (order == 'desc' ? -1 : 1);
      }
    }
    // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications
    // that causes it, under certain circumstances, to provide the same value for
    // `object` and `other`. See https://github.com/jashkenas/underscore/pull/1247
    // for more details.
    //
    // This also ensures a stable sort in V8 and other engines.
    // See https://bugs.chromium.org/p/v8/issues/detail?id=90 for more details.
    return object.index - other.index;
  }

  /**
   * Creates an array that is the composition of partially applied arguments,
   * placeholders, and provided arguments into a single array of arguments.
   *
   * @private
   * @param {Array} args The provided arguments.
   * @param {Array} partials The arguments to prepend to those provided.
   * @param {Array} holders The `partials` placeholder indexes.
   * @params {boolean} [isCurried] Specify composing for a curried function.
   * @returns {Array} Returns the new array of composed arguments.
   */
  function composeArgs(args, partials, holders, isCurried) {
    var argsIndex = -1,
        argsLength = args.length,
        holdersLength = holders.length,
        leftIndex = -1,
        leftLength = partials.length,
        rangeLength = nativeMax(argsLength - holdersLength, 0),
        result = Array(leftLength + rangeLength),
        isUncurried = !isCurried;

    while (++leftIndex < leftLength) {
      result[leftIndex] = partials[leftIndex];
    }
    while (++argsIndex < holdersLength) {
      if (isUncurried || argsIndex < argsLength) {
        result[holders[argsIndex]] = args[argsIndex];
      }
    }
    while (rangeLength--) {
      result[leftIndex++] = args[argsIndex++];
    }
    return result;
  }

  /**
   * This function is like `composeArgs` except that the arguments composition
   * is tailored for `_.partialRight`.
   *
   * @private
   * @param {Array} args The provided arguments.
   * @param {Array} partials The arguments to append to those provided.
   * @param {Array} holders The `partials` placeholder indexes.
   * @params {boolean} [isCurried] Specify composing for a curried function.
   * @returns {Array} Returns the new array of composed arguments.
   */
  function composeArgsRight(args, partials, holders, isCurried) {
    var argsIndex = -1,
        argsLength = args.length,
        holdersIndex = -1,
        holdersLength = holders.length,
        rightIndex = -1,
        rightLength = partials.length,
        rangeLength = nativeMax(argsLength - holdersLength, 0),
        result = Array(rangeLength + rightLength),
        isUncurried = !isCurried;

    while (++argsIndex < rangeLength) {
      result[argsIndex] = args[argsIndex];
    }
    var offset = argsIndex;
    while (++rightIndex < rightLength) {
      result[offset + rightIndex] = partials[rightIndex];
    }
    while (++holdersIndex < holdersLength) {
      if (isUncurried || argsIndex < argsLength) {
        result[offset + holders[holdersIndex]] = args[argsIndex++];
      }
    }
    return result;
  }

  /**
   * Copies the values of `source` to `array`.
   *
   * @private
   * @param {Array} source The array to copy values from.
   * @param {Array} [array=[]] The array to copy values to.
   * @returns {Array} Returns `array`.
   */
  function copyArray(source, array) {
    var index = -1,
        length = source.length;

    array || (array = Array(length));
    while (++index < length) {
      array[index] = source[index];
    }
    return array;
  }

  /**
   * Copies properties of `source` to `object`.
   *
   * @private
   * @param {Object} source The object to copy properties from.
   * @param {Array} props The property identifiers to copy.
   * @param {Object} [object={}] The object to copy properties to.
   * @param {Function} [customizer] The function to customize copied values.
   * @returns {Object} Returns `object`.
   */
  function copyObject(source, props, object, customizer) {
    var isNew = !object;
    object || (object = {});

    var index = -1,
        length = props.length;

    while (++index < length) {
      var key = props[index];

      var newValue = customizer
        ? customizer(object[key], source[key], key, object, source)
        : undefined;

      if (newValue === undefined) {
        newValue = source[key];
      }
      if (isNew) {
        baseAssignValue(object, key, newValue);
      } else {
        assignValue(object, key, newValue);
      }
    }
    return object;
  }

  /**
   * Copies own symbols of `source` to `object`.
   *
   * @private
   * @param {Object} source The object to copy symbols from.
   * @param {Object} [object={}] The object to copy symbols to.
   * @returns {Object} Returns `object`.
   */
  function copySymbols(source, object) {
    return copyObject(source, getSymbols(source), object);
  }

  /**
   * Copies own and inherited symbols of `source` to `object`.
   *
   * @private
   * @param {Object} source The object to copy symbols from.
   * @param {Object} [object={}] The object to copy symbols to.
   * @returns {Object} Returns `object`.
   */
  function copySymbolsIn(source, object) {
    return copyObject(source, getSymbolsIn(source), object);
  }

  /**
   * Creates a function like `_.groupBy`.
   *
   * @private
   * @param {Function} setter The function to set accumulator values.
   * @param {Function} [initializer] The accumulator object initializer.
   * @returns {Function} Returns the new aggregator function.
   */
  function createAggregator(setter, initializer) {
    return function(collection, iteratee) {
      var func = isArray(collection) ? arrayAggregator : baseAggregator,
          accumulator = initializer ? initializer() : {};

      return func(collection, setter, getIteratee(iteratee, 2), accumulator);
    };
  }

  /**
   * Creates a function like `_.assign`.
   *
   * @private
   * @param {Function} assigner The function to assign values.
   * @returns {Function} Returns the new assigner function.
   */
  function createAssigner(assigner) {
    return baseRest(function(object, sources) {
      var index = -1,
          length = sources.length,
          customizer = length > 1 ? sources[length - 1] : undefined,
          guard = length > 2 ? sources[2] : undefined;

      customizer = (assigner.length > 3 && typeof customizer == 'function')
        ? (length--, customizer)
        : undefined;

      if (guard && isIterateeCall(sources[0], sources[1], guard)) {
        customizer = length < 3 ? undefined : customizer;
        length = 1;
      }
      object = Object(object);
      while (++index < length) {
        var source = sources[index];
        if (source) {
          assigner(object, source, index, customizer);
        }
      }
      return object;
    });
  }

  /**
   * Creates a `baseEach` or `baseEachRight` function.
   *
   * @private
   * @param {Function} eachFunc The function to iterate over a collection.
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Function} Returns the new base function.
   */
  function createBaseEach(eachFunc, fromRight) {
    return function(collection, iteratee) {
      if (collection == null) {
        return collection;
      }
      if (!isArrayLike(collection)) {
        return eachFunc(collection, iteratee);
      }
      var length = collection.length,
          index = fromRight ? length : -1,
          iterable = Object(collection);

      while ((fromRight ? index-- : ++index < length)) {
        if (iteratee(iterable[index], index, iterable) === false) {
          break;
        }
      }
      return collection;
    };
  }

  /**
   * Creates a base function for methods like `_.forIn` and `_.forOwn`.
   *
   * @private
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Function} Returns the new base function.
   */
  function createBaseFor(fromRight) {
    return function(object, iteratee, keysFunc) {
      var index = -1,
          iterable = Object(object),
          props = keysFunc(object),
          length = props.length;

      while (length--) {
        var key = props[fromRight ? length : ++index];
        if (iteratee(iterable[key], key, iterable) === false) {
          break;
        }
      }
      return object;
    };
  }

  /**
   * Creates a function that wraps `func` to invoke it with the optional `this`
   * binding of `thisArg`.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @param {*} [thisArg] The `this` binding of `func`.
   * @returns {Function} Returns the new wrapped function.
   */
  function createBind(func, bitmask, thisArg) {
    var isBind = bitmask & WRAP_BIND_FLAG,
        Ctor = createCtor(func);

    function wrapper() {
      var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
      return fn.apply(isBind ? thisArg : this, arguments);
    }
    return wrapper;
  }

  /**
   * Creates a function like `_.lowerFirst`.
   *
   * @private
   * @param {string} methodName The name of the `String` case method to use.
   * @returns {Function} Returns the new case function.
   */
  function createCaseFirst(methodName) {
    return function(string) {
      string = toString(string);

      var strSymbols = hasUnicode(string)
        ? stringToArray(string)
        : undefined;

      var chr = strSymbols
        ? strSymbols[0]
        : string.charAt(0);

      var trailing = strSymbols
        ? castSlice(strSymbols, 1).join('')
        : string.slice(1);

      return chr[methodName]() + trailing;
    };
  }

  /**
   * Creates a function like `_.camelCase`.
   *
   * @private
   * @param {Function} callback The function to combine each word.
   * @returns {Function} Returns the new compounder function.
   */
  function createCompounder(callback) {
    return function(string) {
      return arrayReduce(words(deburr(string).replace(reApos, '')), callback, '');
    };
  }

  /**
   * Creates a function that produces an instance of `Ctor` regardless of
   * whether it was invoked as part of a `new` expression or by `call` or `apply`.
   *
   * @private
   * @param {Function} Ctor The constructor to wrap.
   * @returns {Function} Returns the new wrapped function.
   */
  function createCtor(Ctor) {
    return function() {
      // Use a `switch` statement to work with class constructors. See
      // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist
      // for more details.
      var args = arguments;
      switch (args.length) {
        case 0: return new Ctor;
        case 1: return new Ctor(args[0]);
        case 2: return new Ctor(args[0], args[1]);
        case 3: return new Ctor(args[0], args[1], args[2]);
        case 4: return new Ctor(args[0], args[1], args[2], args[3]);
        case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]);
        case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]);
        case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]);
      }
      var thisBinding = baseCreate(Ctor.prototype),
          result = Ctor.apply(thisBinding, args);

      // Mimic the constructor's `return` behavior.
      // See https://es5.github.io/#x13.2.2 for more details.
      return isObject(result) ? result : thisBinding;
    };
  }

  /**
   * Creates a function that wraps `func` to enable currying.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @param {number} arity The arity of `func`.
   * @returns {Function} Returns the new wrapped function.
   */
  function createCurry(func, bitmask, arity) {
    var Ctor = createCtor(func);

    function wrapper() {
      var length = arguments.length,
          args = Array(length),
          index = length,
          placeholder = getHolder(wrapper);

      while (index--) {
        args[index] = arguments[index];
      }
      var holders = (length < 3 && args[0] !== placeholder && args[length - 1] !== placeholder)
        ? []
        : replaceHolders(args, placeholder);

      length -= holders.length;
      if (length < arity) {
        return createRecurry(
          func, bitmask, createHybrid, wrapper.placeholder, undefined,
          args, holders, undefined, undefined, arity - length);
      }
      var fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
      return apply(fn, this, args);
    }
    return wrapper;
  }

  /**
   * Creates a `_.find` or `_.findLast` function.
   *
   * @private
   * @param {Function} findIndexFunc The function to find the collection index.
   * @returns {Function} Returns the new find function.
   */
  function createFind(findIndexFunc) {
    return function(collection, predicate, fromIndex) {
      var iterable = Object(collection);
      if (!isArrayLike(collection)) {
        var iteratee = getIteratee(predicate, 3);
        collection = keys(collection);
        predicate = function(key) { return iteratee(iterable[key], key, iterable); };
      }
      var index = findIndexFunc(collection, predicate, fromIndex);
      return index > -1 ? iterable[iteratee ? collection[index] : index] : undefined;
    };
  }

  /**
   * Creates a `_.flow` or `_.flowRight` function.
   *
   * @private
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Function} Returns the new flow function.
   */
  function createFlow(fromRight) {
    return flatRest(function(funcs) {
      var length = funcs.length,
          index = length,
          prereq = LodashWrapper.prototype.thru;

      if (fromRight) {
        funcs.reverse();
      }
      while (index--) {
        var func = funcs[index];
        if (typeof func != 'function') {
          throw new TypeError(FUNC_ERROR_TEXT);
        }
        if (prereq && !wrapper && getFuncName(func) == 'wrapper') {
          var wrapper = new LodashWrapper([], true);
        }
      }
      index = wrapper ? index : length;
      while (++index < length) {
        func = funcs[index];

        var funcName = getFuncName(func),
            data = funcName == 'wrapper' ? getData(func) : undefined;

        if (data && isLaziable(data[0]) &&
              data[1] == (WRAP_ARY_FLAG | WRAP_CURRY_FLAG | WRAP_PARTIAL_FLAG | WRAP_REARG_FLAG) &&
              !data[4].length && data[9] == 1
            ) {
          wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]);
        } else {
          wrapper = (func.length == 1 && isLaziable(func))
            ? wrapper[funcName]()
            : wrapper.thru(func);
        }
      }
      return function() {
        var args = arguments,
            value = args[0];

        if (wrapper && args.length == 1 && isArray(value)) {
          return wrapper.plant(value).value();
        }
        var index = 0,
            result = length ? funcs[index].apply(this, args) : value;

        while (++index < length) {
          result = funcs[index].call(this, result);
        }
        return result;
      };
    });
  }

  /**
   * Creates a function that wraps `func` to invoke it with optional `this`
   * binding of `thisArg`, partial application, and currying.
   *
   * @private
   * @param {Function|string} func The function or method name to wrap.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @param {*} [thisArg] The `this` binding of `func`.
   * @param {Array} [partials] The arguments to prepend to those provided to
   *  the new function.
   * @param {Array} [holders] The `partials` placeholder indexes.
   * @param {Array} [partialsRight] The arguments to append to those provided
   *  to the new function.
   * @param {Array} [holdersRight] The `partialsRight` placeholder indexes.
   * @param {Array} [argPos] The argument positions of the new function.
   * @param {number} [ary] The arity cap of `func`.
   * @param {number} [arity] The arity of `func`.
   * @returns {Function} Returns the new wrapped function.
   */
  function createHybrid(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) {
    var isAry = bitmask & WRAP_ARY_FLAG,
        isBind = bitmask & WRAP_BIND_FLAG,
        isBindKey = bitmask & WRAP_BIND_KEY_FLAG,
        isCurried = bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG),
        isFlip = bitmask & WRAP_FLIP_FLAG,
        Ctor = isBindKey ? undefined : createCtor(func);

    function wrapper() {
      var length = arguments.length,
          args = Array(length),
          index = length;

      while (index--) {
        args[index] = arguments[index];
      }
      if (isCurried) {
        var placeholder = getHolder(wrapper),
            holdersCount = countHolders(args, placeholder);
      }
      if (partials) {
        args = composeArgs(args, partials, holders, isCurried);
      }
      if (partialsRight) {
        args = composeArgsRight(args, partialsRight, holdersRight, isCurried);
      }
      length -= holdersCount;
      if (isCurried && length < arity) {
        var newHolders = replaceHolders(args, placeholder);
        return createRecurry(
          func, bitmask, createHybrid, wrapper.placeholder, thisArg,
          args, newHolders, argPos, ary, arity - length
        );
      }
      var thisBinding = isBind ? thisArg : this,
          fn = isBindKey ? thisBinding[func] : func;

      length = args.length;
      if (argPos) {
        args = reorder(args, argPos);
      } else if (isFlip && length > 1) {
        args.reverse();
      }
      if (isAry && ary < length) {
        args.length = ary;
      }
      if (this && this !== root && this instanceof wrapper) {
        fn = Ctor || createCtor(fn);
      }
      return fn.apply(thisBinding, args);
    }
    return wrapper;
  }

  /**
   * Creates a function like `_.invertBy`.
   *
   * @private
   * @param {Function} setter The function to set accumulator values.
   * @param {Function} toIteratee The function to resolve iteratees.
   * @returns {Function} Returns the new inverter function.
   */
  function createInverter(setter, toIteratee) {
    return function(object, iteratee) {
      return baseInverter(object, setter, toIteratee(iteratee), {});
    };
  }

  /**
   * Creates a function that performs a mathematical operation on two values.
   *
   * @private
   * @param {Function} operator The function to perform the operation.
   * @param {number} [defaultValue] The value used for `undefined` arguments.
   * @returns {Function} Returns the new mathematical operation function.
   */
  function createMathOperation(operator, defaultValue) {
    return function(value, other) {
      var result;
      if (value === undefined && other === undefined) {
        return defaultValue;
      }
      if (value !== undefined) {
        result = value;
      }
      if (other !== undefined) {
        if (result === undefined) {
          return other;
        }
        if (typeof value == 'string' || typeof other == 'string') {
          value = baseToString(value);
          other = baseToString(other);
        } else {
          value = baseToNumber(value);
          other = baseToNumber(other);
        }
        result = operator(value, other);
      }
      return result;
    };
  }

  /**
   * Creates a function like `_.over`.
   *
   * @private
   * @param {Function} arrayFunc The function to iterate over iteratees.
   * @returns {Function} Returns the new over function.
   */
  function createOver(arrayFunc) {
    return flatRest(function(iteratees) {
      iteratees = arrayMap(iteratees, baseUnary(getIteratee()));
      return baseRest(function(args) {
        var thisArg = this;
        return arrayFunc(iteratees, function(iteratee) {
          return apply(iteratee, thisArg, args);
        });
      });
    });
  }

  /**
   * Creates the padding for `string` based on `length`. The `chars` string
   * is truncated if the number of characters exceeds `length`.
   *
   * @private
   * @param {number} length The padding length.
   * @param {string} [chars=' '] The string used as padding.
   * @returns {string} Returns the padding for `string`.
   */
  function createPadding(length, chars) {
    chars = chars === undefined ? ' ' : baseToString(chars);

    var charsLength = chars.length;
    if (charsLength < 2) {
      return charsLength ? baseRepeat(chars, length) : chars;
    }
    var result = baseRepeat(chars, nativeCeil(length / stringSize(chars)));
    return hasUnicode(chars)
      ? castSlice(stringToArray(result), 0, length).join('')
      : result.slice(0, length);
  }

  /**
   * Creates a function that wraps `func` to invoke it with the `this` binding
   * of `thisArg` and `partials` prepended to the arguments it receives.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @param {*} thisArg The `this` binding of `func`.
   * @param {Array} partials The arguments to prepend to those provided to
   *  the new function.
   * @returns {Function} Returns the new wrapped function.
   */
  function createPartial(func, bitmask, thisArg, partials) {
    var isBind = bitmask & WRAP_BIND_FLAG,
        Ctor = createCtor(func);

    function wrapper() {
      var argsIndex = -1,
          argsLength = arguments.length,
          leftIndex = -1,
          leftLength = partials.length,
          args = Array(leftLength + argsLength),
          fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;

      while (++leftIndex < leftLength) {
        args[leftIndex] = partials[leftIndex];
      }
      while (argsLength--) {
        args[leftIndex++] = arguments[++argsIndex];
      }
      return apply(fn, isBind ? thisArg : this, args);
    }
    return wrapper;
  }

  /**
   * Creates a `_.range` or `_.rangeRight` function.
   *
   * @private
   * @param {boolean} [fromRight] Specify iterating from right to left.
   * @returns {Function} Returns the new range function.
   */
  function createRange(fromRight) {
    return function(start, end, step) {
      if (step && typeof step != 'number' && isIterateeCall(start, end, step)) {
        end = step = undefined;
      }
      // Ensure the sign of `-0` is preserved.
      start = toFinite(start);
      if (end === undefined) {
        end = start;
        start = 0;
      } else {
        end = toFinite(end);
      }
      step = step === undefined ? (start < end ? 1 : -1) : toFinite(step);
      return baseRange(start, end, step, fromRight);
    };
  }

  /**
   * Creates a function that performs a relational operation on two values.
   *
   * @private
   * @param {Function} operator The function to perform the operation.
   * @returns {Function} Returns the new relational operation function.
   */
  function createRelationalOperation(operator) {
    return function(value, other) {
      if (!(typeof value == 'string' && typeof other == 'string')) {
        value = toNumber(value);
        other = toNumber(other);
      }
      return operator(value, other);
    };
  }

  /**
   * Creates a function that wraps `func` to continue currying.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @param {Function} wrapFunc The function to create the `func` wrapper.
   * @param {*} placeholder The placeholder value.
   * @param {*} [thisArg] The `this` binding of `func`.
   * @param {Array} [partials] The arguments to prepend to those provided to
   *  the new function.
   * @param {Array} [holders] The `partials` placeholder indexes.
   * @param {Array} [argPos] The argument positions of the new function.
   * @param {number} [ary] The arity cap of `func`.
   * @param {number} [arity] The arity of `func`.
   * @returns {Function} Returns the new wrapped function.
   */
  function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) {
    var isCurry = bitmask & WRAP_CURRY_FLAG,
        newHolders = isCurry ? holders : undefined,
        newHoldersRight = isCurry ? undefined : holders,
        newPartials = isCurry ? partials : undefined,
        newPartialsRight = isCurry ? undefined : partials;

    bitmask |= (isCurry ? WRAP_PARTIAL_FLAG : WRAP_PARTIAL_RIGHT_FLAG);
    bitmask &= ~(isCurry ? WRAP_PARTIAL_RIGHT_FLAG : WRAP_PARTIAL_FLAG);

    if (!(bitmask & WRAP_CURRY_BOUND_FLAG)) {
      bitmask &= ~(WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG);
    }
    var newData = [
      func, bitmask, thisArg, newPartials, newHolders, newPartialsRight,
      newHoldersRight, argPos, ary, arity
    ];

    var result = wrapFunc.apply(undefined, newData);
    if (isLaziable(func)) {
      setData(result, newData);
    }
    result.placeholder = placeholder;
    return setWrapToString(result, func, bitmask);
  }

  /**
   * Creates a function like `_.round`.
   *
   * @private
   * @param {string} methodName The name of the `Math` method to use when rounding.
   * @returns {Function} Returns the new round function.
   */
  function createRound(methodName) {
    var func = Math[methodName];
    return function(number, precision) {
      number = toNumber(number);
      precision = precision == null ? 0 : nativeMin(toInteger(precision), 292);
      if (precision && nativeIsFinite(number)) {
        // Shift with exponential notation to avoid floating-point issues.
        // See [MDN](https://mdn.io/round#Examples) for more details.
        var pair = (toString(number) + 'e').split('e'),
            value = func(pair[0] + 'e' + (+pair[1] + precision));

        pair = (toString(value) + 'e').split('e');
        return +(pair[0] + 'e' + (+pair[1] - precision));
      }
      return func(number);
    };
  }

  /**
   * Creates a set object of `values`.
   *
   * @private
   * @param {Array} values The values to add to the set.
   * @returns {Object} Returns the new set.
   */
  var createSet = !(Set && (1 / setToArray(new Set([,-0]))[1]) == INFINITY) ? noop : function(values) {
    return new Set(values);
  };

  /**
   * Creates a `_.toPairs` or `_.toPairsIn` function.
   *
   * @private
   * @param {Function} keysFunc The function to get the keys of a given object.
   * @returns {Function} Returns the new pairs function.
   */
  function createToPairs(keysFunc) {
    return function(object) {
      var tag = getTag(object);
      if (tag == mapTag) {
        return mapToArray(object);
      }
      if (tag == setTag) {
        return setToPairs(object);
      }
      return baseToPairs(object, keysFunc(object));
    };
  }

  /**
   * Creates a function that either curries or invokes `func` with optional
   * `this` binding and partially applied arguments.
   *
   * @private
   * @param {Function|string} func The function or method name to wrap.
   * @param {number} bitmask The bitmask flags.
   *    1 - `_.bind`
   *    2 - `_.bindKey`
   *    4 - `_.curry` or `_.curryRight` of a bound function
   *    8 - `_.curry`
   *   16 - `_.curryRight`
   *   32 - `_.partial`
   *   64 - `_.partialRight`
   *  128 - `_.rearg`
   *  256 - `_.ary`
   *  512 - `_.flip`
   * @param {*} [thisArg] The `this` binding of `func`.
   * @param {Array} [partials] The arguments to be partially applied.
   * @param {Array} [holders] The `partials` placeholder indexes.
   * @param {Array} [argPos] The argument positions of the new function.
   * @param {number} [ary] The arity cap of `func`.
   * @param {number} [arity] The arity of `func`.
   * @returns {Function} Returns the new wrapped function.
   */
  function createWrap(func, bitmask, thisArg, partials, holders, argPos, ary, arity) {
    var isBindKey = bitmask & WRAP_BIND_KEY_FLAG;
    if (!isBindKey && typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    var length = partials ? partials.length : 0;
    if (!length) {
      bitmask &= ~(WRAP_PARTIAL_FLAG | WRAP_PARTIAL_RIGHT_FLAG);
      partials = holders = undefined;
    }
    ary = ary === undefined ? ary : nativeMax(toInteger(ary), 0);
    arity = arity === undefined ? arity : toInteger(arity);
    length -= holders ? holders.length : 0;

    if (bitmask & WRAP_PARTIAL_RIGHT_FLAG) {
      var partialsRight = partials,
          holdersRight = holders;

      partials = holders = undefined;
    }
    var data = isBindKey ? undefined : getData(func);

    var newData = [
      func, bitmask, thisArg, partials, holders, partialsRight, holdersRight,
      argPos, ary, arity
    ];

    if (data) {
      mergeData(newData, data);
    }
    func = newData[0];
    bitmask = newData[1];
    thisArg = newData[2];
    partials = newData[3];
    holders = newData[4];
    arity = newData[9] = newData[9] === undefined
      ? (isBindKey ? 0 : func.length)
      : nativeMax(newData[9] - length, 0);

    if (!arity && bitmask & (WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG)) {
      bitmask &= ~(WRAP_CURRY_FLAG | WRAP_CURRY_RIGHT_FLAG);
    }
    if (!bitmask || bitmask == WRAP_BIND_FLAG) {
      var result = createBind(func, bitmask, thisArg);
    } else if (bitmask == WRAP_CURRY_FLAG || bitmask == WRAP_CURRY_RIGHT_FLAG) {
      result = createCurry(func, bitmask, arity);
    } else if ((bitmask == WRAP_PARTIAL_FLAG || bitmask == (WRAP_BIND_FLAG | WRAP_PARTIAL_FLAG)) && !holders.length) {
      result = createPartial(func, bitmask, thisArg, partials);
    } else {
      result = createHybrid.apply(undefined, newData);
    }
    var setter = data ? baseSetData : setData;
    return setWrapToString(setter(result, newData), func, bitmask);
  }

  /**
   * Used by `_.defaults` to customize its `_.assignIn` use to assign properties
   * of source objects to the destination object for all destination properties
   * that resolve to `undefined`.
   *
   * @private
   * @param {*} objValue The destination value.
   * @param {*} srcValue The source value.
   * @param {string} key The key of the property to assign.
   * @param {Object} object The parent object of `objValue`.
   * @returns {*} Returns the value to assign.
   */
  function customDefaultsAssignIn(objValue, srcValue, key, object) {
    if (objValue === undefined ||
        (eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) {
      return srcValue;
    }
    return objValue;
  }

  /**
   * Used by `_.defaultsDeep` to customize its `_.merge` use to merge source
   * objects into destination objects that are passed thru.
   *
   * @private
   * @param {*} objValue The destination value.
   * @param {*} srcValue The source value.
   * @param {string} key The key of the property to merge.
   * @param {Object} object The parent object of `objValue`.
   * @param {Object} source The parent object of `srcValue`.
   * @param {Object} [stack] Tracks traversed source values and their merged
   *  counterparts.
   * @returns {*} Returns the value to assign.
   */
  function customDefaultsMerge(objValue, srcValue, key, object, source, stack) {
    if (isObject(objValue) && isObject(srcValue)) {
      // Recursively merge objects and arrays (susceptible to call stack limits).
      stack.set(srcValue, objValue);
      baseMerge(objValue, srcValue, undefined, customDefaultsMerge, stack);
      stack['delete'](srcValue);
    }
    return objValue;
  }

  /**
   * Used by `_.omit` to customize its `_.cloneDeep` use to only clone plain
   * objects.
   *
   * @private
   * @param {*} value The value to inspect.
   * @param {string} key The key of the property to inspect.
   * @returns {*} Returns the uncloned value or `undefined` to defer cloning to `_.cloneDeep`.
   */
  function customOmitClone(value) {
    return isPlainObject(value) ? undefined : value;
  }

  /**
   * A specialized version of `baseIsEqualDeep` for arrays with support for
   * partial deep comparisons.
   *
   * @private
   * @param {Array} array The array to compare.
   * @param {Array} other The other array to compare.
   * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
   * @param {Function} customizer The function to customize comparisons.
   * @param {Function} equalFunc The function to determine equivalents of values.
   * @param {Object} stack Tracks traversed `array` and `other` objects.
   * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`.
   */
  function equalArrays(array, other, bitmask, customizer, equalFunc, stack) {
    var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
        arrLength = array.length,
        othLength = other.length;

    if (arrLength != othLength && !(isPartial && othLength > arrLength)) {
      return false;
    }
    // Assume cyclic values are equal.
    var stacked = stack.get(array);
    if (stacked && stack.get(other)) {
      return stacked == other;
    }
    var index = -1,
        result = true,
        seen = (bitmask & COMPARE_UNORDERED_FLAG) ? new SetCache : undefined;

    stack.set(array, other);
    stack.set(other, array);

    // Ignore non-index properties.
    while (++index < arrLength) {
      var arrValue = array[index],
          othValue = other[index];

      if (customizer) {
        var compared = isPartial
          ? customizer(othValue, arrValue, index, other, array, stack)
          : customizer(arrValue, othValue, index, array, other, stack);
      }
      if (compared !== undefined) {
        if (compared) {
          continue;
        }
        result = false;
        break;
      }
      // Recursively compare arrays (susceptible to call stack limits).
      if (seen) {
        if (!arraySome(other, function(othValue, othIndex) {
              if (!cacheHas(seen, othIndex) &&
                  (arrValue === othValue || equalFunc(arrValue, othValue, bitmask, customizer, stack))) {
                return seen.push(othIndex);
              }
            })) {
          result = false;
          break;
        }
      } else if (!(
            arrValue === othValue ||
              equalFunc(arrValue, othValue, bitmask, customizer, stack)
          )) {
        result = false;
        break;
      }
    }
    stack['delete'](array);
    stack['delete'](other);
    return result;
  }

  /**
   * A specialized version of `baseIsEqualDeep` for comparing objects of
   * the same `toStringTag`.
   *
   * **Note:** This function only supports comparing values with tags of
   * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
   *
   * @private
   * @param {Object} object The object to compare.
   * @param {Object} other The other object to compare.
   * @param {string} tag The `toStringTag` of the objects to compare.
   * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
   * @param {Function} customizer The function to customize comparisons.
   * @param {Function} equalFunc The function to determine equivalents of values.
   * @param {Object} stack Tracks traversed `object` and `other` objects.
   * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
   */
  function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) {
    switch (tag) {
      case dataViewTag:
        if ((object.byteLength != other.byteLength) ||
            (object.byteOffset != other.byteOffset)) {
          return false;
        }
        object = object.buffer;
        other = other.buffer;

      case arrayBufferTag:
        if ((object.byteLength != other.byteLength) ||
            !equalFunc(new Uint8Array(object), new Uint8Array(other))) {
          return false;
        }
        return true;

      case boolTag:
      case dateTag:
      case numberTag:
        // Coerce booleans to `1` or `0` and dates to milliseconds.
        // Invalid dates are coerced to `NaN`.
        return eq(+object, +other);

      case errorTag:
        return object.name == other.name && object.message == other.message;

      case regexpTag:
      case stringTag:
        // Coerce regexes to strings and treat strings, primitives and objects,
        // as equal. See http://www.ecma-international.org/ecma-262/7.0/#sec-regexp.prototype.tostring
        // for more details.
        return object == (other + '');

      case mapTag:
        var convert = mapToArray;

      case setTag:
        var isPartial = bitmask & COMPARE_PARTIAL_FLAG;
        convert || (convert = setToArray);

        if (object.size != other.size && !isPartial) {
          return false;
        }
        // Assume cyclic values are equal.
        var stacked = stack.get(object);
        if (stacked) {
          return stacked == other;
        }
        bitmask |= COMPARE_UNORDERED_FLAG;

        // Recursively compare objects (susceptible to call stack limits).
        stack.set(object, other);
        var result = equalArrays(convert(object), convert(other), bitmask, customizer, equalFunc, stack);
        stack['delete'](object);
        return result;

      case symbolTag:
        if (symbolValueOf) {
          return symbolValueOf.call(object) == symbolValueOf.call(other);
        }
    }
    return false;
  }

  /**
   * A specialized version of `baseIsEqualDeep` for objects with support for
   * partial deep comparisons.
   *
   * @private
   * @param {Object} object The object to compare.
   * @param {Object} other The other object to compare.
   * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
   * @param {Function} customizer The function to customize comparisons.
   * @param {Function} equalFunc The function to determine equivalents of values.
   * @param {Object} stack Tracks traversed `object` and `other` objects.
   * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
   */
  function equalObjects(object, other, bitmask, customizer, equalFunc, stack) {
    var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
        objProps = getAllKeys(object),
        objLength = objProps.length,
        othProps = getAllKeys(other),
        othLength = othProps.length;

    if (objLength != othLength && !isPartial) {
      return false;
    }
    var index = objLength;
    while (index--) {
      var key = objProps[index];
      if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) {
        return false;
      }
    }
    // Assume cyclic values are equal.
    var stacked = stack.get(object);
    if (stacked && stack.get(other)) {
      return stacked == other;
    }
    var result = true;
    stack.set(object, other);
    stack.set(other, object);

    var skipCtor = isPartial;
    while (++index < objLength) {
      key = objProps[index];
      var objValue = object[key],
          othValue = other[key];

      if (customizer) {
        var compared = isPartial
          ? customizer(othValue, objValue, key, other, object, stack)
          : customizer(objValue, othValue, key, object, other, stack);
      }
      // Recursively compare objects (susceptible to call stack limits).
      if (!(compared === undefined
            ? (objValue === othValue || equalFunc(objValue, othValue, bitmask, customizer, stack))
            : compared
          )) {
        result = false;
        break;
      }
      skipCtor || (skipCtor = key == 'constructor');
    }
    if (result && !skipCtor) {
      var objCtor = object.constructor,
          othCtor = other.constructor;

      // Non `Object` object instances with different constructors are not equal.
      if (objCtor != othCtor &&
          ('constructor' in object && 'constructor' in other) &&
          !(typeof objCtor == 'function' && objCtor instanceof objCtor &&
            typeof othCtor == 'function' && othCtor instanceof othCtor)) {
        result = false;
      }
    }
    stack['delete'](object);
    stack['delete'](other);
    return result;
  }

  /**
   * A specialized version of `baseRest` which flattens the rest array.
   *
   * @private
   * @param {Function} func The function to apply a rest parameter to.
   * @returns {Function} Returns the new function.
   */
  function flatRest(func) {
    return setToString(overRest(func, undefined, flatten), func + '');
  }

  /**
   * Creates an array of own enumerable property names and symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names and symbols.
   */
  function getAllKeys(object) {
    return baseGetAllKeys(object, keys, getSymbols);
  }

  /**
   * Creates an array of own and inherited enumerable property names and
   * symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names and symbols.
   */
  function getAllKeysIn(object) {
    return baseGetAllKeys(object, keysIn, getSymbolsIn);
  }

  /**
   * Gets metadata for `func`.
   *
   * @private
   * @param {Function} func The function to query.
   * @returns {*} Returns the metadata for `func`.
   */
  var getData = !metaMap ? noop : function(func) {
    return metaMap.get(func);
  };

  /**
   * Gets the name of `func`.
   *
   * @private
   * @param {Function} func The function to query.
   * @returns {string} Returns the function name.
   */
  function getFuncName(func) {
    var result = (func.name + ''),
        array = realNames[result],
        length = hasOwnProperty.call(realNames, result) ? array.length : 0;

    while (length--) {
      var data = array[length],
          otherFunc = data.func;
      if (otherFunc == null || otherFunc == func) {
        return data.name;
      }
    }
    return result;
  }

  /**
   * Gets the argument placeholder value for `func`.
   *
   * @private
   * @param {Function} func The function to inspect.
   * @returns {*} Returns the placeholder value.
   */
  function getHolder(func) {
    var object = hasOwnProperty.call(lodash, 'placeholder') ? lodash : func;
    return object.placeholder;
  }

  /**
   * Gets the appropriate "iteratee" function. If `_.iteratee` is customized,
   * this function returns the custom method, otherwise it returns `baseIteratee`.
   * If arguments are provided, the chosen function is invoked with them and
   * its result is returned.
   *
   * @private
   * @param {*} [value] The value to convert to an iteratee.
   * @param {number} [arity] The arity of the created iteratee.
   * @returns {Function} Returns the chosen function or its result.
   */
  function getIteratee() {
    var result = lodash.iteratee || iteratee;
    result = result === iteratee ? baseIteratee : result;
    return arguments.length ? result(arguments[0], arguments[1]) : result;
  }

  /**
   * Gets the data for `map`.
   *
   * @private
   * @param {Object} map The map to query.
   * @param {string} key The reference key.
   * @returns {*} Returns the map data.
   */
  function getMapData(map, key) {
    var data = map.__data__;
    return isKeyable(key)
      ? data[typeof key == 'string' ? 'string' : 'hash']
      : data.map;
  }

  /**
   * Gets the property names, values, and compare flags of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the match data of `object`.
   */
  function getMatchData(object) {
    var result = keys(object),
        length = result.length;

    while (length--) {
      var key = result[length],
          value = object[key];

      result[length] = [key, value, isStrictComparable(value)];
    }
    return result;
  }

  /**
   * Gets the native function at `key` of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {string} key The key of the method to get.
   * @returns {*} Returns the function if it's native, else `undefined`.
   */
  function getNative(object, key) {
    var value = getValue(object, key);
    return baseIsNative(value) ? value : undefined;
  }

  /**
   * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the raw `toStringTag`.
   */
  function getRawTag(value) {
    var isOwn = hasOwnProperty.call(value, symToStringTag),
        tag = value[symToStringTag];

    try {
      value[symToStringTag] = undefined;
      var unmasked = true;
    } catch (e) {}

    var result = nativeObjectToString.call(value);
    if (unmasked) {
      if (isOwn) {
        value[symToStringTag] = tag;
      } else {
        delete value[symToStringTag];
      }
    }
    return result;
  }

  /**
   * Creates an array of the own enumerable symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of symbols.
   */
  var getSymbols = !nativeGetSymbols ? stubArray : function(object) {
    if (object == null) {
      return [];
    }
    object = Object(object);
    return arrayFilter(nativeGetSymbols(object), function(symbol) {
      return propertyIsEnumerable.call(object, symbol);
    });
  };

  /**
   * Creates an array of the own and inherited enumerable symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of symbols.
   */
  var getSymbolsIn = !nativeGetSymbols ? stubArray : function(object) {
    var result = [];
    while (object) {
      arrayPush(result, getSymbols(object));
      object = getPrototype(object);
    }
    return result;
  };

  /**
   * Gets the `toStringTag` of `value`.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the `toStringTag`.
   */
  var getTag = baseGetTag;

  // Fallback for data views, maps, sets, and weak maps in IE 11 and promises in Node.js < 6.
  if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) ||
      (Map && getTag(new Map) != mapTag) ||
      (Promise && getTag(Promise.resolve()) != promiseTag) ||
      (Set && getTag(new Set) != setTag) ||
      (WeakMap && getTag(new WeakMap) != weakMapTag)) {
    getTag = function(value) {
      var result = baseGetTag(value),
          Ctor = result == objectTag ? value.constructor : undefined,
          ctorString = Ctor ? toSource(Ctor) : '';

      if (ctorString) {
        switch (ctorString) {
          case dataViewCtorString: return dataViewTag;
          case mapCtorString: return mapTag;
          case promiseCtorString: return promiseTag;
          case setCtorString: return setTag;
          case weakMapCtorString: return weakMapTag;
        }
      }
      return result;
    };
  }

  /**
   * Gets the view, applying any `transforms` to the `start` and `end` positions.
   *
   * @private
   * @param {number} start The start of the view.
   * @param {number} end The end of the view.
   * @param {Array} transforms The transformations to apply to the view.
   * @returns {Object} Returns an object containing the `start` and `end`
   *  positions of the view.
   */
  function getView(start, end, transforms) {
    var index = -1,
        length = transforms.length;

    while (++index < length) {
      var data = transforms[index],
          size = data.size;

      switch (data.type) {
        case 'drop':      start += size; break;
        case 'dropRight': end -= size; break;
        case 'take':      end = nativeMin(end, start + size); break;
        case 'takeRight': start = nativeMax(start, end - size); break;
      }
    }
    return { 'start': start, 'end': end };
  }

  /**
   * Extracts wrapper details from the `source` body comment.
   *
   * @private
   * @param {string} source The source to inspect.
   * @returns {Array} Returns the wrapper details.
   */
  function getWrapDetails(source) {
    var match = source.match(reWrapDetails);
    return match ? match[1].split(reSplitDetails) : [];
  }

  /**
   * Checks if `path` exists on `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array|string} path The path to check.
   * @param {Function} hasFunc The function to check properties.
   * @returns {boolean} Returns `true` if `path` exists, else `false`.
   */
  function hasPath(object, path, hasFunc) {
    path = castPath(path, object);

    var index = -1,
        length = path.length,
        result = false;

    while (++index < length) {
      var key = toKey(path[index]);
      if (!(result = object != null && hasFunc(object, key))) {
        break;
      }
      object = object[key];
    }
    if (result || ++index != length) {
      return result;
    }
    length = object == null ? 0 : object.length;
    return !!length && isLength(length) && isIndex(key, length) &&
      (isArray(object) || isArguments(object));
  }

  /**
   * Initializes an array clone.
   *
   * @private
   * @param {Array} array The array to clone.
   * @returns {Array} Returns the initialized clone.
   */
  function initCloneArray(array) {
    var length = array.length,
        result = new array.constructor(length);

    // Add properties assigned by `RegExp#exec`.
    if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) {
      result.index = array.index;
      result.input = array.input;
    }
    return result;
  }

  /**
   * Initializes an object clone.
   *
   * @private
   * @param {Object} object The object to clone.
   * @returns {Object} Returns the initialized clone.
   */
  function initCloneObject(object) {
    return (typeof object.constructor == 'function' && !isPrototype(object))
      ? baseCreate(getPrototype(object))
      : {};
  }

  /**
   * Initializes an object clone based on its `toStringTag`.
   *
   * **Note:** This function only supports cloning values with tags of
   * `Boolean`, `Date`, `Error`, `Map`, `Number`, `RegExp`, `Set`, or `String`.
   *
   * @private
   * @param {Object} object The object to clone.
   * @param {string} tag The `toStringTag` of the object to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the initialized clone.
   */
  function initCloneByTag(object, tag, isDeep) {
    var Ctor = object.constructor;
    switch (tag) {
      case arrayBufferTag:
        return cloneArrayBuffer(object);

      case boolTag:
      case dateTag:
        return new Ctor(+object);

      case dataViewTag:
        return cloneDataView(object, isDeep);

      case float32Tag: case float64Tag:
      case int8Tag: case int16Tag: case int32Tag:
      case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag:
        return cloneTypedArray(object, isDeep);

      case mapTag:
        return new Ctor;

      case numberTag:
      case stringTag:
        return new Ctor(object);

      case regexpTag:
        return cloneRegExp(object);

      case setTag:
        return new Ctor;

      case symbolTag:
        return cloneSymbol(object);
    }
  }

  /**
   * Inserts wrapper `details` in a comment at the top of the `source` body.
   *
   * @private
   * @param {string} source The source to modify.
   * @returns {Array} details The details to insert.
   * @returns {string} Returns the modified source.
   */
  function insertWrapDetails(source, details) {
    var length = details.length;
    if (!length) {
      return source;
    }
    var lastIndex = length - 1;
    details[lastIndex] = (length > 1 ? '& ' : '') + details[lastIndex];
    details = details.join(length > 2 ? ', ' : ' ');
    return source.replace(reWrapComment, '{\n/* [wrapped with ' + details + '] */\n');
  }

  /**
   * Checks if `value` is a flattenable `arguments` object or array.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is flattenable, else `false`.
   */
  function isFlattenable(value) {
    return isArray(value) || isArguments(value) ||
      !!(spreadableSymbol && value && value[spreadableSymbol]);
  }

  /**
   * Checks if `value` is a valid array-like index.
   *
   * @private
   * @param {*} value The value to check.
   * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
   * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
   */
  function isIndex(value, length) {
    var type = typeof value;
    length = length == null ? MAX_SAFE_INTEGER : length;

    return !!length &&
      (type == 'number' ||
        (type != 'symbol' && reIsUint.test(value))) &&
          (value > -1 && value % 1 == 0 && value < length);
  }

  /**
   * Checks if the given arguments are from an iteratee call.
   *
   * @private
   * @param {*} value The potential iteratee value argument.
   * @param {*} index The potential iteratee index or key argument.
   * @param {*} object The potential iteratee object argument.
   * @returns {boolean} Returns `true` if the arguments are from an iteratee call,
   *  else `false`.
   */
  function isIterateeCall(value, index, object) {
    if (!isObject(object)) {
      return false;
    }
    var type = typeof index;
    if (type == 'number'
          ? (isArrayLike(object) && isIndex(index, object.length))
          : (type == 'string' && index in object)
        ) {
      return eq(object[index], value);
    }
    return false;
  }

  /**
   * Checks if `value` is a property name and not a property path.
   *
   * @private
   * @param {*} value The value to check.
   * @param {Object} [object] The object to query keys on.
   * @returns {boolean} Returns `true` if `value` is a property name, else `false`.
   */
  function isKey(value, object) {
    if (isArray(value)) {
      return false;
    }
    var type = typeof value;
    if (type == 'number' || type == 'symbol' || type == 'boolean' ||
        value == null || isSymbol(value)) {
      return true;
    }
    return reIsPlainProp.test(value) || !reIsDeepProp.test(value) ||
      (object != null && value in Object(object));
  }

  /**
   * Checks if `value` is suitable for use as unique object key.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is suitable, else `false`.
   */
  function isKeyable(value) {
    var type = typeof value;
    return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean')
      ? (value !== '__proto__')
      : (value === null);
  }

  /**
   * Checks if `func` has a lazy counterpart.
   *
   * @private
   * @param {Function} func The function to check.
   * @returns {boolean} Returns `true` if `func` has a lazy counterpart,
   *  else `false`.
   */
  function isLaziable(func) {
    var funcName = getFuncName(func),
        other = lodash[funcName];

    if (typeof other != 'function' || !(funcName in LazyWrapper.prototype)) {
      return false;
    }
    if (func === other) {
      return true;
    }
    var data = getData(other);
    return !!data && func === data[0];
  }

  /**
   * Checks if `func` has its source masked.
   *
   * @private
   * @param {Function} func The function to check.
   * @returns {boolean} Returns `true` if `func` is masked, else `false`.
   */
  function isMasked(func) {
    return !!maskSrcKey && (maskSrcKey in func);
  }

  /**
   * Checks if `func` is capable of being masked.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `func` is maskable, else `false`.
   */
  var isMaskable = coreJsData ? isFunction : stubFalse;

  /**
   * Checks if `value` is likely a prototype object.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a prototype, else `false`.
   */
  function isPrototype(value) {
    var Ctor = value && value.constructor,
        proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto;

    return value === proto;
  }

  /**
   * Checks if `value` is suitable for strict equality comparisons, i.e. `===`.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` if suitable for strict
   *  equality comparisons, else `false`.
   */
  function isStrictComparable(value) {
    return value === value && !isObject(value);
  }

  /**
   * A specialized version of `matchesProperty` for source values suitable
   * for strict equality comparisons, i.e. `===`.
   *
   * @private
   * @param {string} key The key of the property to get.
   * @param {*} srcValue The value to match.
   * @returns {Function} Returns the new spec function.
   */
  function matchesStrictComparable(key, srcValue) {
    return function(object) {
      if (object == null) {
        return false;
      }
      return object[key] === srcValue &&
        (srcValue !== undefined || (key in Object(object)));
    };
  }

  /**
   * A specialized version of `_.memoize` which clears the memoized function's
   * cache when it exceeds `MAX_MEMOIZE_SIZE`.
   *
   * @private
   * @param {Function} func The function to have its output memoized.
   * @returns {Function} Returns the new memoized function.
   */
  function memoizeCapped(func) {
    var result = memoize(func, function(key) {
      if (cache.size === MAX_MEMOIZE_SIZE) {
        cache.clear();
      }
      return key;
    });

    var cache = result.cache;
    return result;
  }

  /**
   * Merges the function metadata of `source` into `data`.
   *
   * Merging metadata reduces the number of wrappers used to invoke a function.
   * This is possible because methods like `_.bind`, `_.curry`, and `_.partial`
   * may be applied regardless of execution order. Methods like `_.ary` and
   * `_.rearg` modify function arguments, making the order in which they are
   * executed important, preventing the merging of metadata. However, we make
   * an exception for a safe combined case where curried functions have `_.ary`
   * and or `_.rearg` applied.
   *
   * @private
   * @param {Array} data The destination metadata.
   * @param {Array} source The source metadata.
   * @returns {Array} Returns `data`.
   */
  function mergeData(data, source) {
    var bitmask = data[1],
        srcBitmask = source[1],
        newBitmask = bitmask | srcBitmask,
        isCommon = newBitmask < (WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG | WRAP_ARY_FLAG);

    var isCombo =
      ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_CURRY_FLAG)) ||
      ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_REARG_FLAG) && (data[7].length <= source[8])) ||
      ((srcBitmask == (WRAP_ARY_FLAG | WRAP_REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == WRAP_CURRY_FLAG));

    // Exit early if metadata can't be merged.
    if (!(isCommon || isCombo)) {
      return data;
    }
    // Use source `thisArg` if available.
    if (srcBitmask & WRAP_BIND_FLAG) {
      data[2] = source[2];
      // Set when currying a bound function.
      newBitmask |= bitmask & WRAP_BIND_FLAG ? 0 : WRAP_CURRY_BOUND_FLAG;
    }
    // Compose partial arguments.
    var value = source[3];
    if (value) {
      var partials = data[3];
      data[3] = partials ? composeArgs(partials, value, source[4]) : value;
      data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : source[4];
    }
    // Compose partial right arguments.
    value = source[5];
    if (value) {
      partials = data[5];
      data[5] = partials ? composeArgsRight(partials, value, source[6]) : value;
      data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : source[6];
    }
    // Use source `argPos` if available.
    value = source[7];
    if (value) {
      data[7] = value;
    }
    // Use source `ary` if it's smaller.
    if (srcBitmask & WRAP_ARY_FLAG) {
      data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]);
    }
    // Use source `arity` if one is not provided.
    if (data[9] == null) {
      data[9] = source[9];
    }
    // Use source `func` and merge bitmasks.
    data[0] = source[0];
    data[1] = newBitmask;

    return data;
  }

  /**
   * This function is like
   * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
   * except that it includes inherited enumerable properties.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function nativeKeysIn(object) {
    var result = [];
    if (object != null) {
      for (var key in Object(object)) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * Converts `value` to a string using `Object.prototype.toString`.
   *
   * @private
   * @param {*} value The value to convert.
   * @returns {string} Returns the converted string.
   */
  function objectToString(value) {
    return nativeObjectToString.call(value);
  }

  /**
   * A specialized version of `baseRest` which transforms the rest array.
   *
   * @private
   * @param {Function} func The function to apply a rest parameter to.
   * @param {number} [start=func.length-1] The start position of the rest parameter.
   * @param {Function} transform The rest array transform.
   * @returns {Function} Returns the new function.
   */
  function overRest(func, start, transform) {
    start = nativeMax(start === undefined ? (func.length - 1) : start, 0);
    return function() {
      var args = arguments,
          index = -1,
          length = nativeMax(args.length - start, 0),
          array = Array(length);

      while (++index < length) {
        array[index] = args[start + index];
      }
      index = -1;
      var otherArgs = Array(start + 1);
      while (++index < start) {
        otherArgs[index] = args[index];
      }
      otherArgs[start] = transform(array);
      return apply(func, this, otherArgs);
    };
  }

  /**
   * Gets the parent value at `path` of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array} path The path to get the parent value of.
   * @returns {*} Returns the parent value.
   */
  function parent(object, path) {
    return path.length < 2 ? object : baseGet(object, baseSlice(path, 0, -1));
  }

  /**
   * Reorder `array` according to the specified indexes where the element at
   * the first index is assigned as the first element, the element at
   * the second index is assigned as the second element, and so on.
   *
   * @private
   * @param {Array} array The array to reorder.
   * @param {Array} indexes The arranged array indexes.
   * @returns {Array} Returns `array`.
   */
  function reorder(array, indexes) {
    var arrLength = array.length,
        length = nativeMin(indexes.length, arrLength),
        oldArray = copyArray(array);

    while (length--) {
      var index = indexes[length];
      array[length] = isIndex(index, arrLength) ? oldArray[index] : undefined;
    }
    return array;
  }

  /**
   * Gets the value at `key`, unless `key` is "__proto__" or "constructor".
   *
   * @private
   * @param {Object} object The object to query.
   * @param {string} key The key of the property to get.
   * @returns {*} Returns the property value.
   */
  function safeGet(object, key) {
    if (key === 'constructor' && typeof object[key] === 'function') {
      return;
    }

    if (key == '__proto__') {
      return;
    }

    return object[key];
  }

  /**
   * Sets metadata for `func`.
   *
   * **Note:** If this function becomes hot, i.e. is invoked a lot in a short
   * period of time, it will trip its breaker and transition to an identity
   * function to avoid garbage collection pauses in V8. See
   * [V8 issue 2070](https://bugs.chromium.org/p/v8/issues/detail?id=2070)
   * for more details.
   *
   * @private
   * @param {Function} func The function to associate metadata with.
   * @param {*} data The metadata.
   * @returns {Function} Returns `func`.
   */
  var setData = shortOut(baseSetData);

  /**
   * A simple wrapper around the global [`setTimeout`](https://mdn.io/setTimeout).
   *
   * @private
   * @param {Function} func The function to delay.
   * @param {number} wait The number of milliseconds to delay invocation.
   * @returns {number|Object} Returns the timer id or timeout object.
   */
  var setTimeout = ctxSetTimeout || function(func, wait) {
    return root.setTimeout(func, wait);
  };

  /**
   * Sets the `toString` method of `func` to return `string`.
   *
   * @private
   * @param {Function} func The function to modify.
   * @param {Function} string The `toString` result.
   * @returns {Function} Returns `func`.
   */
  var setToString = shortOut(baseSetToString);

  /**
   * Sets the `toString` method of `wrapper` to mimic the source of `reference`
   * with wrapper details in a comment at the top of the source body.
   *
   * @private
   * @param {Function} wrapper The function to modify.
   * @param {Function} reference The reference function.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @returns {Function} Returns `wrapper`.
   */
  function setWrapToString(wrapper, reference, bitmask) {
    var source = (reference + '');
    return setToString(wrapper, insertWrapDetails(source, updateWrapDetails(getWrapDetails(source), bitmask)));
  }

  /**
   * Creates a function that'll short out and invoke `identity` instead
   * of `func` when it's called `HOT_COUNT` or more times in `HOT_SPAN`
   * milliseconds.
   *
   * @private
   * @param {Function} func The function to restrict.
   * @returns {Function} Returns the new shortable function.
   */
  function shortOut(func) {
    var count = 0,
        lastCalled = 0;

    return function() {
      var stamp = nativeNow(),
          remaining = HOT_SPAN - (stamp - lastCalled);

      lastCalled = stamp;
      if (remaining > 0) {
        if (++count >= HOT_COUNT) {
          return arguments[0];
        }
      } else {
        count = 0;
      }
      return func.apply(undefined, arguments);
    };
  }

  /**
   * A specialized version of `_.shuffle` which mutates and sets the size of `array`.
   *
   * @private
   * @param {Array} array The array to shuffle.
   * @param {number} [size=array.length] The size of `array`.
   * @returns {Array} Returns `array`.
   */
  function shuffleSelf(array, size) {
    var index = -1,
        length = array.length,
        lastIndex = length - 1;

    size = size === undefined ? length : size;
    while (++index < size) {
      var rand = baseRandom(index, lastIndex),
          value = array[rand];

      array[rand] = array[index];
      array[index] = value;
    }
    array.length = size;
    return array;
  }

  /**
   * Converts `string` to a property path array.
   *
   * @private
   * @param {string} string The string to convert.
   * @returns {Array} Returns the property path array.
   */
  var stringToPath = memoizeCapped(function(string) {
    var result = [];
    if (string.charCodeAt(0) === 46 /* . */) {
      result.push('');
    }
    string.replace(rePropName, function(match, number, quote, subString) {
      result.push(quote ? subString.replace(reEscapeChar, '$1') : (number || match));
    });
    return result;
  });

  /**
   * Converts `value` to a string key if it's not a string or symbol.
   *
   * @private
   * @param {*} value The value to inspect.
   * @returns {string|symbol} Returns the key.
   */
  function toKey(value) {
    if (typeof value == 'string' || isSymbol(value)) {
      return value;
    }
    var result = (value + '');
    return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
  }

  /**
   * Converts `func` to its source code.
   *
   * @private
   * @param {Function} func The function to convert.
   * @returns {string} Returns the source code.
   */
  function toSource(func) {
    if (func != null) {
      try {
        return funcToString.call(func);
      } catch (e) {}
      try {
        return (func + '');
      } catch (e) {}
    }
    return '';
  }

  /**
   * Updates wrapper `details` based on `bitmask` flags.
   *
   * @private
   * @returns {Array} details The details to modify.
   * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
   * @returns {Array} Returns `details`.
   */
  function updateWrapDetails(details, bitmask) {
    arrayEach(wrapFlags, function(pair) {
      var value = '_.' + pair[0];
      if ((bitmask & pair[1]) && !arrayIncludes(details, value)) {
        details.push(value);
      }
    });
    return details.sort();
  }

  /**
   * Creates a clone of `wrapper`.
   *
   * @private
   * @param {Object} wrapper The wrapper to clone.
   * @returns {Object} Returns the cloned wrapper.
   */
  function wrapperClone(wrapper) {
    if (wrapper instanceof LazyWrapper) {
      return wrapper.clone();
    }
    var result = new LodashWrapper(wrapper.__wrapped__, wrapper.__chain__);
    result.__actions__ = copyArray(wrapper.__actions__);
    result.__index__  = wrapper.__index__;
    result.__values__ = wrapper.__values__;
    return result;
  }

  /*------------------------------------------------------------------------*/

  /**
   * Creates an array of elements split into groups the length of `size`.
   * If `array` can't be split evenly, the final chunk will be the remaining
   * elements.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to process.
   * @param {number} [size=1] The length of each chunk
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the new array of chunks.
   * @example
   *
   * _.chunk(['a', 'b', 'c', 'd'], 2);
   * // => [['a', 'b'], ['c', 'd']]
   *
   * _.chunk(['a', 'b', 'c', 'd'], 3);
   * // => [['a', 'b', 'c'], ['d']]
   */
  function chunk(array, size, guard) {
    if ((guard ? isIterateeCall(array, size, guard) : size === undefined)) {
      size = 1;
    } else {
      size = nativeMax(toInteger(size), 0);
    }
    var length = array == null ? 0 : array.length;
    if (!length || size < 1) {
      return [];
    }
    var index = 0,
        resIndex = 0,
        result = Array(nativeCeil(length / size));

    while (index < length) {
      result[resIndex++] = baseSlice(array, index, (index += size));
    }
    return result;
  }

  /**
   * Creates an array with all falsey values removed. The values `false`, `null`,
   * `0`, `""`, `undefined`, and `NaN` are falsey.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to compact.
   * @returns {Array} Returns the new array of filtered values.
   * @example
   *
   * _.compact([0, 1, false, 2, '', 3]);
   * // => [1, 2, 3]
   */
  function compact(array) {
    var index = -1,
        length = array == null ? 0 : array.length,
        resIndex = 0,
        result = [];

    while (++index < length) {
      var value = array[index];
      if (value) {
        result[resIndex++] = value;
      }
    }
    return result;
  }

  /**
   * Creates a new array concatenating `array` with any additional arrays
   * and/or values.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to concatenate.
   * @param {...*} [values] The values to concatenate.
   * @returns {Array} Returns the new concatenated array.
   * @example
   *
   * var array = [1];
   * var other = _.concat(array, 2, [3], [[4]]);
   *
   * console.log(other);
   * // => [1, 2, 3, [4]]
   *
   * console.log(array);
   * // => [1]
   */
  function concat() {
    var length = arguments.length;
    if (!length) {
      return [];
    }
    var args = Array(length - 1),
        array = arguments[0],
        index = length;

    while (index--) {
      args[index - 1] = arguments[index];
    }
    return arrayPush(isArray(array) ? copyArray(array) : [array], baseFlatten(args, 1));
  }

  /**
   * Creates an array of `array` values not included in the other given arrays
   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons. The order and references of result values are
   * determined by the first array.
   *
   * **Note:** Unlike `_.pullAll`, this method returns a new array.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {...Array} [values] The values to exclude.
   * @returns {Array} Returns the new array of filtered values.
   * @see _.without, _.xor
   * @example
   *
   * _.difference([2, 1], [2, 3]);
   * // => [1]
   */
  var difference = baseRest(function(array, values) {
    return isArrayLikeObject(array)
      ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true))
      : [];
  });

  /**
   * This method is like `_.difference` except that it accepts `iteratee` which
   * is invoked for each element of `array` and `values` to generate the criterion
   * by which they're compared. The order and references of result values are
   * determined by the first array. The iteratee is invoked with one argument:
   * (value).
   *
   * **Note:** Unlike `_.pullAllBy`, this method returns a new array.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {...Array} [values] The values to exclude.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns the new array of filtered values.
   * @example
   *
   * _.differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor);
   * // => [1.2]
   *
   * // The `_.property` iteratee shorthand.
   * _.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x');
   * // => [{ 'x': 2 }]
   */
  var differenceBy = baseRest(function(array, values) {
    var iteratee = last(values);
    if (isArrayLikeObject(iteratee)) {
      iteratee = undefined;
    }
    return isArrayLikeObject(array)
      ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), getIteratee(iteratee, 2))
      : [];
  });

  /**
   * This method is like `_.difference` except that it accepts `comparator`
   * which is invoked to compare elements of `array` to `values`. The order and
   * references of result values are determined by the first array. The comparator
   * is invoked with two arguments: (arrVal, othVal).
   *
   * **Note:** Unlike `_.pullAllWith`, this method returns a new array.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {...Array} [values] The values to exclude.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of filtered values.
   * @example
   *
   * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
   *
   * _.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual);
   * // => [{ 'x': 2, 'y': 1 }]
   */
  var differenceWith = baseRest(function(array, values) {
    var comparator = last(values);
    if (isArrayLikeObject(comparator)) {
      comparator = undefined;
    }
    return isArrayLikeObject(array)
      ? baseDifference(array, baseFlatten(values, 1, isArrayLikeObject, true), undefined, comparator)
      : [];
  });

  /**
   * Creates a slice of `array` with `n` elements dropped from the beginning.
   *
   * @static
   * @memberOf _
   * @since 0.5.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {number} [n=1] The number of elements to drop.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.drop([1, 2, 3]);
   * // => [2, 3]
   *
   * _.drop([1, 2, 3], 2);
   * // => [3]
   *
   * _.drop([1, 2, 3], 5);
   * // => []
   *
   * _.drop([1, 2, 3], 0);
   * // => [1, 2, 3]
   */
  function drop(array, n, guard) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    n = (guard || n === undefined) ? 1 : toInteger(n);
    return baseSlice(array, n < 0 ? 0 : n, length);
  }

  /**
   * Creates a slice of `array` with `n` elements dropped from the end.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {number} [n=1] The number of elements to drop.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.dropRight([1, 2, 3]);
   * // => [1, 2]
   *
   * _.dropRight([1, 2, 3], 2);
   * // => [1]
   *
   * _.dropRight([1, 2, 3], 5);
   * // => []
   *
   * _.dropRight([1, 2, 3], 0);
   * // => [1, 2, 3]
   */
  function dropRight(array, n, guard) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    n = (guard || n === undefined) ? 1 : toInteger(n);
    n = length - n;
    return baseSlice(array, 0, n < 0 ? 0 : n);
  }

  /**
   * Creates a slice of `array` excluding elements dropped from the end.
   * Elements are dropped until `predicate` returns falsey. The predicate is
   * invoked with three arguments: (value, index, array).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': true },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': false }
   * ];
   *
   * _.dropRightWhile(users, function(o) { return !o.active; });
   * // => objects for ['barney']
   *
   * // The `_.matches` iteratee shorthand.
   * _.dropRightWhile(users, { 'user': 'pebbles', 'active': false });
   * // => objects for ['barney', 'fred']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.dropRightWhile(users, ['active', false]);
   * // => objects for ['barney']
   *
   * // The `_.property` iteratee shorthand.
   * _.dropRightWhile(users, 'active');
   * // => objects for ['barney', 'fred', 'pebbles']
   */
  function dropRightWhile(array, predicate) {
    return (array && array.length)
      ? baseWhile(array, getIteratee(predicate, 3), true, true)
      : [];
  }

  /**
   * Creates a slice of `array` excluding elements dropped from the beginning.
   * Elements are dropped until `predicate` returns falsey. The predicate is
   * invoked with three arguments: (value, index, array).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': false },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': true }
   * ];
   *
   * _.dropWhile(users, function(o) { return !o.active; });
   * // => objects for ['pebbles']
   *
   * // The `_.matches` iteratee shorthand.
   * _.dropWhile(users, { 'user': 'barney', 'active': false });
   * // => objects for ['fred', 'pebbles']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.dropWhile(users, ['active', false]);
   * // => objects for ['pebbles']
   *
   * // The `_.property` iteratee shorthand.
   * _.dropWhile(users, 'active');
   * // => objects for ['barney', 'fred', 'pebbles']
   */
  function dropWhile(array, predicate) {
    return (array && array.length)
      ? baseWhile(array, getIteratee(predicate, 3), true)
      : [];
  }

  /**
   * Fills elements of `array` with `value` from `start` up to, but not
   * including, `end`.
   *
   * **Note:** This method mutates `array`.
   *
   * @static
   * @memberOf _
   * @since 3.2.0
   * @category Array
   * @param {Array} array The array to fill.
   * @param {*} value The value to fill `array` with.
   * @param {number} [start=0] The start position.
   * @param {number} [end=array.length] The end position.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = [1, 2, 3];
   *
   * _.fill(array, 'a');
   * console.log(array);
   * // => ['a', 'a', 'a']
   *
   * _.fill(Array(3), 2);
   * // => [2, 2, 2]
   *
   * _.fill([4, 6, 8, 10], '*', 1, 3);
   * // => [4, '*', '*', 10]
   */
  function fill(array, value, start, end) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    if (start && typeof start != 'number' && isIterateeCall(array, value, start)) {
      start = 0;
      end = length;
    }
    return baseFill(array, value, start, end);
  }

  /**
   * This method is like `_.find` except that it returns the index of the first
   * element `predicate` returns truthy for instead of the element itself.
   *
   * @static
   * @memberOf _
   * @since 1.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param {number} [fromIndex=0] The index to search from.
   * @returns {number} Returns the index of the found element, else `-1`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': false },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': true }
   * ];
   *
   * _.findIndex(users, function(o) { return o.user == 'barney'; });
   * // => 0
   *
   * // The `_.matches` iteratee shorthand.
   * _.findIndex(users, { 'user': 'fred', 'active': false });
   * // => 1
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.findIndex(users, ['active', false]);
   * // => 0
   *
   * // The `_.property` iteratee shorthand.
   * _.findIndex(users, 'active');
   * // => 2
   */
  function findIndex(array, predicate, fromIndex) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return -1;
    }
    var index = fromIndex == null ? 0 : toInteger(fromIndex);
    if (index < 0) {
      index = nativeMax(length + index, 0);
    }
    return baseFindIndex(array, getIteratee(predicate, 3), index);
  }

  /**
   * This method is like `_.findIndex` except that it iterates over elements
   * of `collection` from right to left.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param {number} [fromIndex=array.length-1] The index to search from.
   * @returns {number} Returns the index of the found element, else `-1`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': true },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': false }
   * ];
   *
   * _.findLastIndex(users, function(o) { return o.user == 'pebbles'; });
   * // => 2
   *
   * // The `_.matches` iteratee shorthand.
   * _.findLastIndex(users, { 'user': 'barney', 'active': true });
   * // => 0
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.findLastIndex(users, ['active', false]);
   * // => 2
   *
   * // The `_.property` iteratee shorthand.
   * _.findLastIndex(users, 'active');
   * // => 0
   */
  function findLastIndex(array, predicate, fromIndex) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return -1;
    }
    var index = length - 1;
    if (fromIndex !== undefined) {
      index = toInteger(fromIndex);
      index = fromIndex < 0
        ? nativeMax(length + index, 0)
        : nativeMin(index, length - 1);
    }
    return baseFindIndex(array, getIteratee(predicate, 3), index, true);
  }

  /**
   * Flattens `array` a single level deep.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to flatten.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * _.flatten([1, [2, [3, [4]], 5]]);
   * // => [1, 2, [3, [4]], 5]
   */
  function flatten(array) {
    var length = array == null ? 0 : array.length;
    return length ? baseFlatten(array, 1) : [];
  }

  /**
   * Recursively flattens `array`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to flatten.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * _.flattenDeep([1, [2, [3, [4]], 5]]);
   * // => [1, 2, 3, 4, 5]
   */
  function flattenDeep(array) {
    var length = array == null ? 0 : array.length;
    return length ? baseFlatten(array, INFINITY) : [];
  }

  /**
   * Recursively flatten `array` up to `depth` times.
   *
   * @static
   * @memberOf _
   * @since 4.4.0
   * @category Array
   * @param {Array} array The array to flatten.
   * @param {number} [depth=1] The maximum recursion depth.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * var array = [1, [2, [3, [4]], 5]];
   *
   * _.flattenDepth(array, 1);
   * // => [1, 2, [3, [4]], 5]
   *
   * _.flattenDepth(array, 2);
   * // => [1, 2, 3, [4], 5]
   */
  function flattenDepth(array, depth) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    depth = depth === undefined ? 1 : toInteger(depth);
    return baseFlatten(array, depth);
  }

  /**
   * The inverse of `_.toPairs`; this method returns an object composed
   * from key-value `pairs`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} pairs The key-value pairs.
   * @returns {Object} Returns the new object.
   * @example
   *
   * _.fromPairs([['a', 1], ['b', 2]]);
   * // => { 'a': 1, 'b': 2 }
   */
  function fromPairs(pairs) {
    var index = -1,
        length = pairs == null ? 0 : pairs.length,
        result = {};

    while (++index < length) {
      var pair = pairs[index];
      result[pair[0]] = pair[1];
    }
    return result;
  }

  /**
   * Gets the first element of `array`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @alias first
   * @category Array
   * @param {Array} array The array to query.
   * @returns {*} Returns the first element of `array`.
   * @example
   *
   * _.head([1, 2, 3]);
   * // => 1
   *
   * _.head([]);
   * // => undefined
   */
  function head(array) {
    return (array && array.length) ? array[0] : undefined;
  }

  /**
   * Gets the index at which the first occurrence of `value` is found in `array`
   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons. If `fromIndex` is negative, it's used as the
   * offset from the end of `array`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} [fromIndex=0] The index to search from.
   * @returns {number} Returns the index of the matched value, else `-1`.
   * @example
   *
   * _.indexOf([1, 2, 1, 2], 2);
   * // => 1
   *
   * // Search from the `fromIndex`.
   * _.indexOf([1, 2, 1, 2], 2, 2);
   * // => 3
   */
  function indexOf(array, value, fromIndex) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return -1;
    }
    var index = fromIndex == null ? 0 : toInteger(fromIndex);
    if (index < 0) {
      index = nativeMax(length + index, 0);
    }
    return baseIndexOf(array, value, index);
  }

  /**
   * Gets all but the last element of `array`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to query.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.initial([1, 2, 3]);
   * // => [1, 2]
   */
  function initial(array) {
    var length = array == null ? 0 : array.length;
    return length ? baseSlice(array, 0, -1) : [];
  }

  /**
   * Creates an array of unique values that are included in all given arrays
   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons. The order and references of result values are
   * determined by the first array.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @returns {Array} Returns the new array of intersecting values.
   * @example
   *
   * _.intersection([2, 1], [2, 3]);
   * // => [2]
   */
  var intersection = baseRest(function(arrays) {
    var mapped = arrayMap(arrays, castArrayLikeObject);
    return (mapped.length && mapped[0] === arrays[0])
      ? baseIntersection(mapped)
      : [];
  });

  /**
   * This method is like `_.intersection` except that it accepts `iteratee`
   * which is invoked for each element of each `arrays` to generate the criterion
   * by which they're compared. The order and references of result values are
   * determined by the first array. The iteratee is invoked with one argument:
   * (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns the new array of intersecting values.
   * @example
   *
   * _.intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor);
   * // => [2.1]
   *
   * // The `_.property` iteratee shorthand.
   * _.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
   * // => [{ 'x': 1 }]
   */
  var intersectionBy = baseRest(function(arrays) {
    var iteratee = last(arrays),
        mapped = arrayMap(arrays, castArrayLikeObject);

    if (iteratee === last(mapped)) {
      iteratee = undefined;
    } else {
      mapped.pop();
    }
    return (mapped.length && mapped[0] === arrays[0])
      ? baseIntersection(mapped, getIteratee(iteratee, 2))
      : [];
  });

  /**
   * This method is like `_.intersection` except that it accepts `comparator`
   * which is invoked to compare elements of `arrays`. The order and references
   * of result values are determined by the first array. The comparator is
   * invoked with two arguments: (arrVal, othVal).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of intersecting values.
   * @example
   *
   * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
   * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
   *
   * _.intersectionWith(objects, others, _.isEqual);
   * // => [{ 'x': 1, 'y': 2 }]
   */
  var intersectionWith = baseRest(function(arrays) {
    var comparator = last(arrays),
        mapped = arrayMap(arrays, castArrayLikeObject);

    comparator = typeof comparator == 'function' ? comparator : undefined;
    if (comparator) {
      mapped.pop();
    }
    return (mapped.length && mapped[0] === arrays[0])
      ? baseIntersection(mapped, undefined, comparator)
      : [];
  });

  /**
   * Converts all elements in `array` into a string separated by `separator`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to convert.
   * @param {string} [separator=','] The element separator.
   * @returns {string} Returns the joined string.
   * @example
   *
   * _.join(['a', 'b', 'c'], '~');
   * // => 'a~b~c'
   */
  function join(array, separator) {
    return array == null ? '' : nativeJoin.call(array, separator);
  }

  /**
   * Gets the last element of `array`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to query.
   * @returns {*} Returns the last element of `array`.
   * @example
   *
   * _.last([1, 2, 3]);
   * // => 3
   */
  function last(array) {
    var length = array == null ? 0 : array.length;
    return length ? array[length - 1] : undefined;
  }

  /**
   * This method is like `_.indexOf` except that it iterates over elements of
   * `array` from right to left.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @param {number} [fromIndex=array.length-1] The index to search from.
   * @returns {number} Returns the index of the matched value, else `-1`.
   * @example
   *
   * _.lastIndexOf([1, 2, 1, 2], 2);
   * // => 3
   *
   * // Search from the `fromIndex`.
   * _.lastIndexOf([1, 2, 1, 2], 2, 2);
   * // => 1
   */
  function lastIndexOf(array, value, fromIndex) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return -1;
    }
    var index = length;
    if (fromIndex !== undefined) {
      index = toInteger(fromIndex);
      index = index < 0 ? nativeMax(length + index, 0) : nativeMin(index, length - 1);
    }
    return value === value
      ? strictLastIndexOf(array, value, index)
      : baseFindIndex(array, baseIsNaN, index, true);
  }

  /**
   * Gets the element at index `n` of `array`. If `n` is negative, the nth
   * element from the end is returned.
   *
   * @static
   * @memberOf _
   * @since 4.11.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {number} [n=0] The index of the element to return.
   * @returns {*} Returns the nth element of `array`.
   * @example
   *
   * var array = ['a', 'b', 'c', 'd'];
   *
   * _.nth(array, 1);
   * // => 'b'
   *
   * _.nth(array, -2);
   * // => 'c';
   */
  function nth(array, n) {
    return (array && array.length) ? baseNth(array, toInteger(n)) : undefined;
  }

  /**
   * Removes all given values from `array` using
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons.
   *
   * **Note:** Unlike `_.without`, this method mutates `array`. Use `_.remove`
   * to remove elements from an array by predicate.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {...*} [values] The values to remove.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = ['a', 'b', 'c', 'a', 'b', 'c'];
   *
   * _.pull(array, 'a', 'c');
   * console.log(array);
   * // => ['b', 'b']
   */
  var pull = baseRest(pullAll);

  /**
   * This method is like `_.pull` except that it accepts an array of values to remove.
   *
   * **Note:** Unlike `_.difference`, this method mutates `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {Array} values The values to remove.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = ['a', 'b', 'c', 'a', 'b', 'c'];
   *
   * _.pullAll(array, ['a', 'c']);
   * console.log(array);
   * // => ['b', 'b']
   */
  function pullAll(array, values) {
    return (array && array.length && values && values.length)
      ? basePullAll(array, values)
      : array;
  }

  /**
   * This method is like `_.pullAll` except that it accepts `iteratee` which is
   * invoked for each element of `array` and `values` to generate the criterion
   * by which they're compared. The iteratee is invoked with one argument: (value).
   *
   * **Note:** Unlike `_.differenceBy`, this method mutates `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {Array} values The values to remove.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }];
   *
   * _.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x');
   * console.log(array);
   * // => [{ 'x': 2 }]
   */
  function pullAllBy(array, values, iteratee) {
    return (array && array.length && values && values.length)
      ? basePullAll(array, values, getIteratee(iteratee, 2))
      : array;
  }

  /**
   * This method is like `_.pullAll` except that it accepts `comparator` which
   * is invoked to compare elements of `array` to `values`. The comparator is
   * invoked with two arguments: (arrVal, othVal).
   *
   * **Note:** Unlike `_.differenceWith`, this method mutates `array`.
   *
   * @static
   * @memberOf _
   * @since 4.6.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {Array} values The values to remove.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = [{ 'x': 1, 'y': 2 }, { 'x': 3, 'y': 4 }, { 'x': 5, 'y': 6 }];
   *
   * _.pullAllWith(array, [{ 'x': 3, 'y': 4 }], _.isEqual);
   * console.log(array);
   * // => [{ 'x': 1, 'y': 2 }, { 'x': 5, 'y': 6 }]
   */
  function pullAllWith(array, values, comparator) {
    return (array && array.length && values && values.length)
      ? basePullAll(array, values, undefined, comparator)
      : array;
  }

  /**
   * Removes elements from `array` corresponding to `indexes` and returns an
   * array of removed elements.
   *
   * **Note:** Unlike `_.at`, this method mutates `array`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {...(number|number[])} [indexes] The indexes of elements to remove.
   * @returns {Array} Returns the new array of removed elements.
   * @example
   *
   * var array = ['a', 'b', 'c', 'd'];
   * var pulled = _.pullAt(array, [1, 3]);
   *
   * console.log(array);
   * // => ['a', 'c']
   *
   * console.log(pulled);
   * // => ['b', 'd']
   */
  var pullAt = flatRest(function(array, indexes) {
    var length = array == null ? 0 : array.length,
        result = baseAt(array, indexes);

    basePullAt(array, arrayMap(indexes, function(index) {
      return isIndex(index, length) ? +index : index;
    }).sort(compareAscending));

    return result;
  });

  /**
   * Removes all elements from `array` that `predicate` returns truthy for
   * and returns an array of the removed elements. The predicate is invoked
   * with three arguments: (value, index, array).
   *
   * **Note:** Unlike `_.filter`, this method mutates `array`. Use `_.pull`
   * to pull elements from an array by value.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new array of removed elements.
   * @example
   *
   * var array = [1, 2, 3, 4];
   * var evens = _.remove(array, function(n) {
   *   return n % 2 == 0;
   * });
   *
   * console.log(array);
   * // => [1, 3]
   *
   * console.log(evens);
   * // => [2, 4]
   */
  function remove(array, predicate) {
    var result = [];
    if (!(array && array.length)) {
      return result;
    }
    var index = -1,
        indexes = [],
        length = array.length;

    predicate = getIteratee(predicate, 3);
    while (++index < length) {
      var value = array[index];
      if (predicate(value, index, array)) {
        result.push(value);
        indexes.push(index);
      }
    }
    basePullAt(array, indexes);
    return result;
  }

  /**
   * Reverses `array` so that the first element becomes the last, the second
   * element becomes the second to last, and so on.
   *
   * **Note:** This method mutates `array` and is based on
   * [`Array#reverse`](https://mdn.io/Array/reverse).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to modify.
   * @returns {Array} Returns `array`.
   * @example
   *
   * var array = [1, 2, 3];
   *
   * _.reverse(array);
   * // => [3, 2, 1]
   *
   * console.log(array);
   * // => [3, 2, 1]
   */
  function reverse(array) {
    return array == null ? array : nativeReverse.call(array);
  }

  /**
   * Creates a slice of `array` from `start` up to, but not including, `end`.
   *
   * **Note:** This method is used instead of
   * [`Array#slice`](https://mdn.io/Array/slice) to ensure dense arrays are
   * returned.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to slice.
   * @param {number} [start=0] The start position.
   * @param {number} [end=array.length] The end position.
   * @returns {Array} Returns the slice of `array`.
   */
  function slice(array, start, end) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    if (end && typeof end != 'number' && isIterateeCall(array, start, end)) {
      start = 0;
      end = length;
    }
    else {
      start = start == null ? 0 : toInteger(start);
      end = end === undefined ? length : toInteger(end);
    }
    return baseSlice(array, start, end);
  }

  /**
   * Uses a binary search to determine the lowest index at which `value`
   * should be inserted into `array` in order to maintain its sort order.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   * @example
   *
   * _.sortedIndex([30, 50], 40);
   * // => 1
   */
  function sortedIndex(array, value) {
    return baseSortedIndex(array, value);
  }

  /**
   * This method is like `_.sortedIndex` except that it accepts `iteratee`
   * which is invoked for `value` and each element of `array` to compute their
   * sort ranking. The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   * @example
   *
   * var objects = [{ 'x': 4 }, { 'x': 5 }];
   *
   * _.sortedIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
   * // => 0
   *
   * // The `_.property` iteratee shorthand.
   * _.sortedIndexBy(objects, { 'x': 4 }, 'x');
   * // => 0
   */
  function sortedIndexBy(array, value, iteratee) {
    return baseSortedIndexBy(array, value, getIteratee(iteratee, 2));
  }

  /**
   * This method is like `_.indexOf` except that it performs a binary
   * search on a sorted `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @returns {number} Returns the index of the matched value, else `-1`.
   * @example
   *
   * _.sortedIndexOf([4, 5, 5, 5, 6], 5);
   * // => 1
   */
  function sortedIndexOf(array, value) {
    var length = array == null ? 0 : array.length;
    if (length) {
      var index = baseSortedIndex(array, value);
      if (index < length && eq(array[index], value)) {
        return index;
      }
    }
    return -1;
  }

  /**
   * This method is like `_.sortedIndex` except that it returns the highest
   * index at which `value` should be inserted into `array` in order to
   * maintain its sort order.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   * @example
   *
   * _.sortedLastIndex([4, 5, 5, 5, 6], 5);
   * // => 4
   */
  function sortedLastIndex(array, value) {
    return baseSortedIndex(array, value, true);
  }

  /**
   * This method is like `_.sortedLastIndex` except that it accepts `iteratee`
   * which is invoked for `value` and each element of `array` to compute their
   * sort ranking. The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The sorted array to inspect.
   * @param {*} value The value to evaluate.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {number} Returns the index at which `value` should be inserted
   *  into `array`.
   * @example
   *
   * var objects = [{ 'x': 4 }, { 'x': 5 }];
   *
   * _.sortedLastIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
   * // => 1
   *
   * // The `_.property` iteratee shorthand.
   * _.sortedLastIndexBy(objects, { 'x': 4 }, 'x');
   * // => 1
   */
  function sortedLastIndexBy(array, value, iteratee) {
    return baseSortedIndexBy(array, value, getIteratee(iteratee, 2), true);
  }

  /**
   * This method is like `_.lastIndexOf` except that it performs a binary
   * search on a sorted `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {*} value The value to search for.
   * @returns {number} Returns the index of the matched value, else `-1`.
   * @example
   *
   * _.sortedLastIndexOf([4, 5, 5, 5, 6], 5);
   * // => 3
   */
  function sortedLastIndexOf(array, value) {
    var length = array == null ? 0 : array.length;
    if (length) {
      var index = baseSortedIndex(array, value, true) - 1;
      if (eq(array[index], value)) {
        return index;
      }
    }
    return -1;
  }

  /**
   * This method is like `_.uniq` except that it's designed and optimized
   * for sorted arrays.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @returns {Array} Returns the new duplicate free array.
   * @example
   *
   * _.sortedUniq([1, 1, 2]);
   * // => [1, 2]
   */
  function sortedUniq(array) {
    return (array && array.length)
      ? baseSortedUniq(array)
      : [];
  }

  /**
   * This method is like `_.uniqBy` except that it's designed and optimized
   * for sorted arrays.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {Function} [iteratee] The iteratee invoked per element.
   * @returns {Array} Returns the new duplicate free array.
   * @example
   *
   * _.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor);
   * // => [1.1, 2.3]
   */
  function sortedUniqBy(array, iteratee) {
    return (array && array.length)
      ? baseSortedUniq(array, getIteratee(iteratee, 2))
      : [];
  }

  /**
   * Gets all but the first element of `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.tail([1, 2, 3]);
   * // => [2, 3]
   */
  function tail(array) {
    var length = array == null ? 0 : array.length;
    return length ? baseSlice(array, 1, length) : [];
  }

  /**
   * Creates a slice of `array` with `n` elements taken from the beginning.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {number} [n=1] The number of elements to take.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.take([1, 2, 3]);
   * // => [1]
   *
   * _.take([1, 2, 3], 2);
   * // => [1, 2]
   *
   * _.take([1, 2, 3], 5);
   * // => [1, 2, 3]
   *
   * _.take([1, 2, 3], 0);
   * // => []
   */
  function take(array, n, guard) {
    if (!(array && array.length)) {
      return [];
    }
    n = (guard || n === undefined) ? 1 : toInteger(n);
    return baseSlice(array, 0, n < 0 ? 0 : n);
  }

  /**
   * Creates a slice of `array` with `n` elements taken from the end.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {number} [n=1] The number of elements to take.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * _.takeRight([1, 2, 3]);
   * // => [3]
   *
   * _.takeRight([1, 2, 3], 2);
   * // => [2, 3]
   *
   * _.takeRight([1, 2, 3], 5);
   * // => [1, 2, 3]
   *
   * _.takeRight([1, 2, 3], 0);
   * // => []
   */
  function takeRight(array, n, guard) {
    var length = array == null ? 0 : array.length;
    if (!length) {
      return [];
    }
    n = (guard || n === undefined) ? 1 : toInteger(n);
    n = length - n;
    return baseSlice(array, n < 0 ? 0 : n, length);
  }

  /**
   * Creates a slice of `array` with elements taken from the end. Elements are
   * taken until `predicate` returns falsey. The predicate is invoked with
   * three arguments: (value, index, array).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': true },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': false }
   * ];
   *
   * _.takeRightWhile(users, function(o) { return !o.active; });
   * // => objects for ['fred', 'pebbles']
   *
   * // The `_.matches` iteratee shorthand.
   * _.takeRightWhile(users, { 'user': 'pebbles', 'active': false });
   * // => objects for ['pebbles']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.takeRightWhile(users, ['active', false]);
   * // => objects for ['fred', 'pebbles']
   *
   * // The `_.property` iteratee shorthand.
   * _.takeRightWhile(users, 'active');
   * // => []
   */
  function takeRightWhile(array, predicate) {
    return (array && array.length)
      ? baseWhile(array, getIteratee(predicate, 3), false, true)
      : [];
  }

  /**
   * Creates a slice of `array` with elements taken from the beginning. Elements
   * are taken until `predicate` returns falsey. The predicate is invoked with
   * three arguments: (value, index, array).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Array
   * @param {Array} array The array to query.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the slice of `array`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'active': false },
   *   { 'user': 'fred',    'active': false },
   *   { 'user': 'pebbles', 'active': true }
   * ];
   *
   * _.takeWhile(users, function(o) { return !o.active; });
   * // => objects for ['barney', 'fred']
   *
   * // The `_.matches` iteratee shorthand.
   * _.takeWhile(users, { 'user': 'barney', 'active': false });
   * // => objects for ['barney']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.takeWhile(users, ['active', false]);
   * // => objects for ['barney', 'fred']
   *
   * // The `_.property` iteratee shorthand.
   * _.takeWhile(users, 'active');
   * // => []
   */
  function takeWhile(array, predicate) {
    return (array && array.length)
      ? baseWhile(array, getIteratee(predicate, 3))
      : [];
  }

  /**
   * Creates an array of unique values, in order, from all given arrays using
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @returns {Array} Returns the new array of combined values.
   * @example
   *
   * _.union([2], [1, 2]);
   * // => [2, 1]
   */
  var union = baseRest(function(arrays) {
    return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true));
  });

  /**
   * This method is like `_.union` except that it accepts `iteratee` which is
   * invoked for each element of each `arrays` to generate the criterion by
   * which uniqueness is computed. Result values are chosen from the first
   * array in which the value occurs. The iteratee is invoked with one argument:
   * (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns the new array of combined values.
   * @example
   *
   * _.unionBy([2.1], [1.2, 2.3], Math.floor);
   * // => [2.1, 1.2]
   *
   * // The `_.property` iteratee shorthand.
   * _.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
   * // => [{ 'x': 1 }, { 'x': 2 }]
   */
  var unionBy = baseRest(function(arrays) {
    var iteratee = last(arrays);
    if (isArrayLikeObject(iteratee)) {
      iteratee = undefined;
    }
    return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), getIteratee(iteratee, 2));
  });

  /**
   * This method is like `_.union` except that it accepts `comparator` which
   * is invoked to compare elements of `arrays`. Result values are chosen from
   * the first array in which the value occurs. The comparator is invoked
   * with two arguments: (arrVal, othVal).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of combined values.
   * @example
   *
   * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
   * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
   *
   * _.unionWith(objects, others, _.isEqual);
   * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
   */
  var unionWith = baseRest(function(arrays) {
    var comparator = last(arrays);
    comparator = typeof comparator == 'function' ? comparator : undefined;
    return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), undefined, comparator);
  });

  /**
   * Creates a duplicate-free version of an array, using
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons, in which only the first occurrence of each element
   * is kept. The order of result values is determined by the order they occur
   * in the array.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @returns {Array} Returns the new duplicate free array.
   * @example
   *
   * _.uniq([2, 1, 2]);
   * // => [2, 1]
   */
  function uniq(array) {
    return (array && array.length) ? baseUniq(array) : [];
  }

  /**
   * This method is like `_.uniq` except that it accepts `iteratee` which is
   * invoked for each element in `array` to generate the criterion by which
   * uniqueness is computed. The order of result values is determined by the
   * order they occur in the array. The iteratee is invoked with one argument:
   * (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns the new duplicate free array.
   * @example
   *
   * _.uniqBy([2.1, 1.2, 2.3], Math.floor);
   * // => [2.1, 1.2]
   *
   * // The `_.property` iteratee shorthand.
   * _.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
   * // => [{ 'x': 1 }, { 'x': 2 }]
   */
  function uniqBy(array, iteratee) {
    return (array && array.length) ? baseUniq(array, getIteratee(iteratee, 2)) : [];
  }

  /**
   * This method is like `_.uniq` except that it accepts `comparator` which
   * is invoked to compare elements of `array`. The order of result values is
   * determined by the order they occur in the array.The comparator is invoked
   * with two arguments: (arrVal, othVal).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new duplicate free array.
   * @example
   *
   * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }];
   *
   * _.uniqWith(objects, _.isEqual);
   * // => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]
   */
  function uniqWith(array, comparator) {
    comparator = typeof comparator == 'function' ? comparator : undefined;
    return (array && array.length) ? baseUniq(array, undefined, comparator) : [];
  }

  /**
   * This method is like `_.zip` except that it accepts an array of grouped
   * elements and creates an array regrouping the elements to their pre-zip
   * configuration.
   *
   * @static
   * @memberOf _
   * @since 1.2.0
   * @category Array
   * @param {Array} array The array of grouped elements to process.
   * @returns {Array} Returns the new array of regrouped elements.
   * @example
   *
   * var zipped = _.zip(['a', 'b'], [1, 2], [true, false]);
   * // => [['a', 1, true], ['b', 2, false]]
   *
   * _.unzip(zipped);
   * // => [['a', 'b'], [1, 2], [true, false]]
   */
  function unzip(array) {
    if (!(array && array.length)) {
      return [];
    }
    var length = 0;
    array = arrayFilter(array, function(group) {
      if (isArrayLikeObject(group)) {
        length = nativeMax(group.length, length);
        return true;
      }
    });
    return baseTimes(length, function(index) {
      return arrayMap(array, baseProperty(index));
    });
  }

  /**
   * This method is like `_.unzip` except that it accepts `iteratee` to specify
   * how regrouped values should be combined. The iteratee is invoked with the
   * elements of each group: (...group).
   *
   * @static
   * @memberOf _
   * @since 3.8.0
   * @category Array
   * @param {Array} array The array of grouped elements to process.
   * @param {Function} [iteratee=_.identity] The function to combine
   *  regrouped values.
   * @returns {Array} Returns the new array of regrouped elements.
   * @example
   *
   * var zipped = _.zip([1, 2], [10, 20], [100, 200]);
   * // => [[1, 10, 100], [2, 20, 200]]
   *
   * _.unzipWith(zipped, _.add);
   * // => [3, 30, 300]
   */
  function unzipWith(array, iteratee) {
    if (!(array && array.length)) {
      return [];
    }
    var result = unzip(array);
    if (iteratee == null) {
      return result;
    }
    return arrayMap(result, function(group) {
      return apply(iteratee, undefined, group);
    });
  }

  /**
   * Creates an array excluding all given values using
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons.
   *
   * **Note:** Unlike `_.pull`, this method returns a new array.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {Array} array The array to inspect.
   * @param {...*} [values] The values to exclude.
   * @returns {Array} Returns the new array of filtered values.
   * @see _.difference, _.xor
   * @example
   *
   * _.without([2, 1, 2, 3], 1, 2);
   * // => [3]
   */
  var without = baseRest(function(array, values) {
    return isArrayLikeObject(array)
      ? baseDifference(array, values)
      : [];
  });

  /**
   * Creates an array of unique values that is the
   * [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference)
   * of the given arrays. The order of result values is determined by the order
   * they occur in the arrays.
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @returns {Array} Returns the new array of filtered values.
   * @see _.difference, _.without
   * @example
   *
   * _.xor([2, 1], [2, 3]);
   * // => [1, 3]
   */
  var xor = baseRest(function(arrays) {
    return baseXor(arrayFilter(arrays, isArrayLikeObject));
  });

  /**
   * This method is like `_.xor` except that it accepts `iteratee` which is
   * invoked for each element of each `arrays` to generate the criterion by
   * which by which they're compared. The order of result values is determined
   * by the order they occur in the arrays. The iteratee is invoked with one
   * argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Array} Returns the new array of filtered values.
   * @example
   *
   * _.xorBy([2.1, 1.2], [2.3, 3.4], Math.floor);
   * // => [1.2, 3.4]
   *
   * // The `_.property` iteratee shorthand.
   * _.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
   * // => [{ 'x': 2 }]
   */
  var xorBy = baseRest(function(arrays) {
    var iteratee = last(arrays);
    if (isArrayLikeObject(iteratee)) {
      iteratee = undefined;
    }
    return baseXor(arrayFilter(arrays, isArrayLikeObject), getIteratee(iteratee, 2));
  });

  /**
   * This method is like `_.xor` except that it accepts `comparator` which is
   * invoked to compare elements of `arrays`. The order of result values is
   * determined by the order they occur in the arrays. The comparator is invoked
   * with two arguments: (arrVal, othVal).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Array
   * @param {...Array} [arrays] The arrays to inspect.
   * @param {Function} [comparator] The comparator invoked per element.
   * @returns {Array} Returns the new array of filtered values.
   * @example
   *
   * var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
   * var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
   *
   * _.xorWith(objects, others, _.isEqual);
   * // => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
   */
  var xorWith = baseRest(function(arrays) {
    var comparator = last(arrays);
    comparator = typeof comparator == 'function' ? comparator : undefined;
    return baseXor(arrayFilter(arrays, isArrayLikeObject), undefined, comparator);
  });

  /**
   * Creates an array of grouped elements, the first of which contains the
   * first elements of the given arrays, the second of which contains the
   * second elements of the given arrays, and so on.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Array
   * @param {...Array} [arrays] The arrays to process.
   * @returns {Array} Returns the new array of grouped elements.
   * @example
   *
   * _.zip(['a', 'b'], [1, 2], [true, false]);
   * // => [['a', 1, true], ['b', 2, false]]
   */
  var zip = baseRest(unzip);

  /**
   * This method is like `_.fromPairs` except that it accepts two arrays,
   * one of property identifiers and one of corresponding values.
   *
   * @static
   * @memberOf _
   * @since 0.4.0
   * @category Array
   * @param {Array} [props=[]] The property identifiers.
   * @param {Array} [values=[]] The property values.
   * @returns {Object} Returns the new object.
   * @example
   *
   * _.zipObject(['a', 'b'], [1, 2]);
   * // => { 'a': 1, 'b': 2 }
   */
  function zipObject(props, values) {
    return baseZipObject(props || [], values || [], assignValue);
  }

  /**
   * This method is like `_.zipObject` except that it supports property paths.
   *
   * @static
   * @memberOf _
   * @since 4.1.0
   * @category Array
   * @param {Array} [props=[]] The property identifiers.
   * @param {Array} [values=[]] The property values.
   * @returns {Object} Returns the new object.
   * @example
   *
   * _.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]);
   * // => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } }
   */
  function zipObjectDeep(props, values) {
    return baseZipObject(props || [], values || [], baseSet);
  }

  /**
   * This method is like `_.zip` except that it accepts `iteratee` to specify
   * how grouped values should be combined. The iteratee is invoked with the
   * elements of each group: (...group).
   *
   * @static
   * @memberOf _
   * @since 3.8.0
   * @category Array
   * @param {...Array} [arrays] The arrays to process.
   * @param {Function} [iteratee=_.identity] The function to combine
   *  grouped values.
   * @returns {Array} Returns the new array of grouped elements.
   * @example
   *
   * _.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) {
   *   return a + b + c;
   * });
   * // => [111, 222]
   */
  var zipWith = baseRest(function(arrays) {
    var length = arrays.length,
        iteratee = length > 1 ? arrays[length - 1] : undefined;

    iteratee = typeof iteratee == 'function' ? (arrays.pop(), iteratee) : undefined;
    return unzipWith(arrays, iteratee);
  });

  /*------------------------------------------------------------------------*/

  /**
   * Creates a `lodash` wrapper instance that wraps `value` with explicit method
   * chain sequences enabled. The result of such sequences must be unwrapped
   * with `_#value`.
   *
   * @static
   * @memberOf _
   * @since 1.3.0
   * @category Seq
   * @param {*} value The value to wrap.
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'age': 36 },
   *   { 'user': 'fred',    'age': 40 },
   *   { 'user': 'pebbles', 'age': 1 }
   * ];
   *
   * var youngest = _
   *   .chain(users)
   *   .sortBy('age')
   *   .map(function(o) {
   *     return o.user + ' is ' + o.age;
   *   })
   *   .head()
   *   .value();
   * // => 'pebbles is 1'
   */
  function chain(value) {
    var result = lodash(value);
    result.__chain__ = true;
    return result;
  }

  /**
   * This method invokes `interceptor` and returns `value`. The interceptor
   * is invoked with one argument; (value). The purpose of this method is to
   * "tap into" a method chain sequence in order to modify intermediate results.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Seq
   * @param {*} value The value to provide to `interceptor`.
   * @param {Function} interceptor The function to invoke.
   * @returns {*} Returns `value`.
   * @example
   *
   * _([1, 2, 3])
   *  .tap(function(array) {
   *    // Mutate input array.
   *    array.pop();
   *  })
   *  .reverse()
   *  .value();
   * // => [2, 1]
   */
  function tap(value, interceptor) {
    interceptor(value);
    return value;
  }

  /**
   * This method is like `_.tap` except that it returns the result of `interceptor`.
   * The purpose of this method is to "pass thru" values replacing intermediate
   * results in a method chain sequence.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Seq
   * @param {*} value The value to provide to `interceptor`.
   * @param {Function} interceptor The function to invoke.
   * @returns {*} Returns the result of `interceptor`.
   * @example
   *
   * _('  abc  ')
   *  .chain()
   *  .trim()
   *  .thru(function(value) {
   *    return [value];
   *  })
   *  .value();
   * // => ['abc']
   */
  function thru(value, interceptor) {
    return interceptor(value);
  }

  /**
   * This method is the wrapper version of `_.at`.
   *
   * @name at
   * @memberOf _
   * @since 1.0.0
   * @category Seq
   * @param {...(string|string[])} [paths] The property paths to pick.
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
   *
   * _(object).at(['a[0].b.c', 'a[1]']).value();
   * // => [3, 4]
   */
  var wrapperAt = flatRest(function(paths) {
    var length = paths.length,
        start = length ? paths[0] : 0,
        value = this.__wrapped__,
        interceptor = function(object) { return baseAt(object, paths); };

    if (length > 1 || this.__actions__.length ||
        !(value instanceof LazyWrapper) || !isIndex(start)) {
      return this.thru(interceptor);
    }
    value = value.slice(start, +start + (length ? 1 : 0));
    value.__actions__.push({
      'func': thru,
      'args': [interceptor],
      'thisArg': undefined
    });
    return new LodashWrapper(value, this.__chain__).thru(function(array) {
      if (length && !array.length) {
        array.push(undefined);
      }
      return array;
    });
  });

  /**
   * Creates a `lodash` wrapper instance with explicit method chain sequences enabled.
   *
   * @name chain
   * @memberOf _
   * @since 0.1.0
   * @category Seq
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * var users = [
   *   { 'user': 'barney', 'age': 36 },
   *   { 'user': 'fred',   'age': 40 }
   * ];
   *
   * // A sequence without explicit chaining.
   * _(users).head();
   * // => { 'user': 'barney', 'age': 36 }
   *
   * // A sequence with explicit chaining.
   * _(users)
   *   .chain()
   *   .head()
   *   .pick('user')
   *   .value();
   * // => { 'user': 'barney' }
   */
  function wrapperChain() {
    return chain(this);
  }

  /**
   * Executes the chain sequence and returns the wrapped result.
   *
   * @name commit
   * @memberOf _
   * @since 3.2.0
   * @category Seq
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * var array = [1, 2];
   * var wrapped = _(array).push(3);
   *
   * console.log(array);
   * // => [1, 2]
   *
   * wrapped = wrapped.commit();
   * console.log(array);
   * // => [1, 2, 3]
   *
   * wrapped.last();
   * // => 3
   *
   * console.log(array);
   * // => [1, 2, 3]
   */
  function wrapperCommit() {
    return new LodashWrapper(this.value(), this.__chain__);
  }

  /**
   * Gets the next value on a wrapped object following the
   * [iterator protocol](https://mdn.io/iteration_protocols#iterator).
   *
   * @name next
   * @memberOf _
   * @since 4.0.0
   * @category Seq
   * @returns {Object} Returns the next iterator value.
   * @example
   *
   * var wrapped = _([1, 2]);
   *
   * wrapped.next();
   * // => { 'done': false, 'value': 1 }
   *
   * wrapped.next();
   * // => { 'done': false, 'value': 2 }
   *
   * wrapped.next();
   * // => { 'done': true, 'value': undefined }
   */
  function wrapperNext() {
    if (this.__values__ === undefined) {
      this.__values__ = toArray(this.value());
    }
    var done = this.__index__ >= this.__values__.length,
        value = done ? undefined : this.__values__[this.__index__++];

    return { 'done': done, 'value': value };
  }

  /**
   * Enables the wrapper to be iterable.
   *
   * @name Symbol.iterator
   * @memberOf _
   * @since 4.0.0
   * @category Seq
   * @returns {Object} Returns the wrapper object.
   * @example
   *
   * var wrapped = _([1, 2]);
   *
   * wrapped[Symbol.iterator]() === wrapped;
   * // => true
   *
   * Array.from(wrapped);
   * // => [1, 2]
   */
  function wrapperToIterator() {
    return this;
  }

  /**
   * Creates a clone of the chain sequence planting `value` as the wrapped value.
   *
   * @name plant
   * @memberOf _
   * @since 3.2.0
   * @category Seq
   * @param {*} value The value to plant.
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var wrapped = _([1, 2]).map(square);
   * var other = wrapped.plant([3, 4]);
   *
   * other.value();
   * // => [9, 16]
   *
   * wrapped.value();
   * // => [1, 4]
   */
  function wrapperPlant(value) {
    var result,
        parent = this;

    while (parent instanceof baseLodash) {
      var clone = wrapperClone(parent);
      clone.__index__ = 0;
      clone.__values__ = undefined;
      if (result) {
        previous.__wrapped__ = clone;
      } else {
        result = clone;
      }
      var previous = clone;
      parent = parent.__wrapped__;
    }
    previous.__wrapped__ = value;
    return result;
  }

  /**
   * This method is the wrapper version of `_.reverse`.
   *
   * **Note:** This method mutates the wrapped array.
   *
   * @name reverse
   * @memberOf _
   * @since 0.1.0
   * @category Seq
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * var array = [1, 2, 3];
   *
   * _(array).reverse().value()
   * // => [3, 2, 1]
   *
   * console.log(array);
   * // => [3, 2, 1]
   */
  function wrapperReverse() {
    var value = this.__wrapped__;
    if (value instanceof LazyWrapper) {
      var wrapped = value;
      if (this.__actions__.length) {
        wrapped = new LazyWrapper(this);
      }
      wrapped = wrapped.reverse();
      wrapped.__actions__.push({
        'func': thru,
        'args': [reverse],
        'thisArg': undefined
      });
      return new LodashWrapper(wrapped, this.__chain__);
    }
    return this.thru(reverse);
  }

  /**
   * Executes the chain sequence to resolve the unwrapped value.
   *
   * @name value
   * @memberOf _
   * @since 0.1.0
   * @alias toJSON, valueOf
   * @category Seq
   * @returns {*} Returns the resolved unwrapped value.
   * @example
   *
   * _([1, 2, 3]).value();
   * // => [1, 2, 3]
   */
  function wrapperValue() {
    return baseWrapperValue(this.__wrapped__, this.__actions__);
  }

  /*------------------------------------------------------------------------*/

  /**
   * Creates an object composed of keys generated from the results of running
   * each element of `collection` thru `iteratee`. The corresponding value of
   * each key is the number of times the key was returned by `iteratee`. The
   * iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 0.5.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
   * @returns {Object} Returns the composed aggregate object.
   * @example
   *
   * _.countBy([6.1, 4.2, 6.3], Math.floor);
   * // => { '4': 1, '6': 2 }
   *
   * // The `_.property` iteratee shorthand.
   * _.countBy(['one', 'two', 'three'], 'length');
   * // => { '3': 2, '5': 1 }
   */
  var countBy = createAggregator(function(result, value, key) {
    if (hasOwnProperty.call(result, key)) {
      ++result[key];
    } else {
      baseAssignValue(result, key, 1);
    }
  });

  /**
   * Checks if `predicate` returns truthy for **all** elements of `collection`.
   * Iteration is stopped once `predicate` returns falsey. The predicate is
   * invoked with three arguments: (value, index|key, collection).
   *
   * **Note:** This method returns `true` for
   * [empty collections](https://en.wikipedia.org/wiki/Empty_set) because
   * [everything is true](https://en.wikipedia.org/wiki/Vacuous_truth) of
   * elements of empty collections.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {boolean} Returns `true` if all elements pass the predicate check,
   *  else `false`.
   * @example
   *
   * _.every([true, 1, null, 'yes'], Boolean);
   * // => false
   *
   * var users = [
   *   { 'user': 'barney', 'age': 36, 'active': false },
   *   { 'user': 'fred',   'age': 40, 'active': false }
   * ];
   *
   * // The `_.matches` iteratee shorthand.
   * _.every(users, { 'user': 'barney', 'active': false });
   * // => false
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.every(users, ['active', false]);
   * // => true
   *
   * // The `_.property` iteratee shorthand.
   * _.every(users, 'active');
   * // => false
   */
  function every(collection, predicate, guard) {
    var func = isArray(collection) ? arrayEvery : baseEvery;
    if (guard && isIterateeCall(collection, predicate, guard)) {
      predicate = undefined;
    }
    return func(collection, getIteratee(predicate, 3));
  }

  /**
   * Iterates over elements of `collection`, returning an array of all elements
   * `predicate` returns truthy for. The predicate is invoked with three
   * arguments: (value, index|key, collection).
   *
   * **Note:** Unlike `_.remove`, this method returns a new array.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new filtered array.
   * @see _.reject
   * @example
   *
   * var users = [
   *   { 'user': 'barney', 'age': 36, 'active': true },
   *   { 'user': 'fred',   'age': 40, 'active': false }
   * ];
   *
   * _.filter(users, function(o) { return !o.active; });
   * // => objects for ['fred']
   *
   * // The `_.matches` iteratee shorthand.
   * _.filter(users, { 'age': 36, 'active': true });
   * // => objects for ['barney']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.filter(users, ['active', false]);
   * // => objects for ['fred']
   *
   * // The `_.property` iteratee shorthand.
   * _.filter(users, 'active');
   * // => objects for ['barney']
   */
  function filter(collection, predicate) {
    var func = isArray(collection) ? arrayFilter : baseFilter;
    return func(collection, getIteratee(predicate, 3));
  }

  /**
   * Iterates over elements of `collection`, returning the first element
   * `predicate` returns truthy for. The predicate is invoked with three
   * arguments: (value, index|key, collection).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param {number} [fromIndex=0] The index to search from.
   * @returns {*} Returns the matched element, else `undefined`.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'age': 36, 'active': true },
   *   { 'user': 'fred',    'age': 40, 'active': false },
   *   { 'user': 'pebbles', 'age': 1,  'active': true }
   * ];
   *
   * _.find(users, function(o) { return o.age < 40; });
   * // => object for 'barney'
   *
   * // The `_.matches` iteratee shorthand.
   * _.find(users, { 'age': 1, 'active': true });
   * // => object for 'pebbles'
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.find(users, ['active', false]);
   * // => object for 'fred'
   *
   * // The `_.property` iteratee shorthand.
   * _.find(users, 'active');
   * // => object for 'barney'
   */
  var find = createFind(findIndex);

  /**
   * This method is like `_.find` except that it iterates over elements of
   * `collection` from right to left.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param {number} [fromIndex=collection.length-1] The index to search from.
   * @returns {*} Returns the matched element, else `undefined`.
   * @example
   *
   * _.findLast([1, 2, 3, 4], function(n) {
   *   return n % 2 == 1;
   * });
   * // => 3
   */
  var findLast = createFind(findLastIndex);

  /**
   * Creates a flattened array of values by running each element in `collection`
   * thru `iteratee` and flattening the mapped results. The iteratee is invoked
   * with three arguments: (value, index|key, collection).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * function duplicate(n) {
   *   return [n, n];
   * }
   *
   * _.flatMap([1, 2], duplicate);
   * // => [1, 1, 2, 2]
   */
  function flatMap(collection, iteratee) {
    return baseFlatten(map(collection, iteratee), 1);
  }

  /**
   * This method is like `_.flatMap` except that it recursively flattens the
   * mapped results.
   *
   * @static
   * @memberOf _
   * @since 4.7.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * function duplicate(n) {
   *   return [[[n, n]]];
   * }
   *
   * _.flatMapDeep([1, 2], duplicate);
   * // => [1, 1, 2, 2]
   */
  function flatMapDeep(collection, iteratee) {
    return baseFlatten(map(collection, iteratee), INFINITY);
  }

  /**
   * This method is like `_.flatMap` except that it recursively flattens the
   * mapped results up to `depth` times.
   *
   * @static
   * @memberOf _
   * @since 4.7.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @param {number} [depth=1] The maximum recursion depth.
   * @returns {Array} Returns the new flattened array.
   * @example
   *
   * function duplicate(n) {
   *   return [[[n, n]]];
   * }
   *
   * _.flatMapDepth([1, 2], duplicate, 2);
   * // => [[1, 1], [2, 2]]
   */
  function flatMapDepth(collection, iteratee, depth) {
    depth = depth === undefined ? 1 : toInteger(depth);
    return baseFlatten(map(collection, iteratee), depth);
  }

  /**
   * Iterates over elements of `collection` and invokes `iteratee` for each element.
   * The iteratee is invoked with three arguments: (value, index|key, collection).
   * Iteratee functions may exit iteration early by explicitly returning `false`.
   *
   * **Note:** As with other "Collections" methods, objects with a "length"
   * property are iterated like arrays. To avoid this behavior use `_.forIn`
   * or `_.forOwn` for object iteration.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @alias each
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array|Object} Returns `collection`.
   * @see _.forEachRight
   * @example
   *
   * _.forEach([1, 2], function(value) {
   *   console.log(value);
   * });
   * // => Logs `1` then `2`.
   *
   * _.forEach({ 'a': 1, 'b': 2 }, function(value, key) {
   *   console.log(key);
   * });
   * // => Logs 'a' then 'b' (iteration order is not guaranteed).
   */
  function forEach(collection, iteratee) {
    var func = isArray(collection) ? arrayEach : baseEach;
    return func(collection, getIteratee(iteratee, 3));
  }

  /**
   * This method is like `_.forEach` except that it iterates over elements of
   * `collection` from right to left.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @alias eachRight
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array|Object} Returns `collection`.
   * @see _.forEach
   * @example
   *
   * _.forEachRight([1, 2], function(value) {
   *   console.log(value);
   * });
   * // => Logs `2` then `1`.
   */
  function forEachRight(collection, iteratee) {
    var func = isArray(collection) ? arrayEachRight : baseEachRight;
    return func(collection, getIteratee(iteratee, 3));
  }

  /**
   * Creates an object composed of keys generated from the results of running
   * each element of `collection` thru `iteratee`. The order of grouped values
   * is determined by the order they occur in `collection`. The corresponding
   * value of each key is an array of elements responsible for generating the
   * key. The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
   * @returns {Object} Returns the composed aggregate object.
   * @example
   *
   * _.groupBy([6.1, 4.2, 6.3], Math.floor);
   * // => { '4': [4.2], '6': [6.1, 6.3] }
   *
   * // The `_.property` iteratee shorthand.
   * _.groupBy(['one', 'two', 'three'], 'length');
   * // => { '3': ['one', 'two'], '5': ['three'] }
   */
  var groupBy = createAggregator(function(result, value, key) {
    if (hasOwnProperty.call(result, key)) {
      result[key].push(value);
    } else {
      baseAssignValue(result, key, [value]);
    }
  });

  /**
   * Checks if `value` is in `collection`. If `collection` is a string, it's
   * checked for a substring of `value`, otherwise
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * is used for equality comparisons. If `fromIndex` is negative, it's used as
   * the offset from the end of `collection`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object|string} collection The collection to inspect.
   * @param {*} value The value to search for.
   * @param {number} [fromIndex=0] The index to search from.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`.
   * @returns {boolean} Returns `true` if `value` is found, else `false`.
   * @example
   *
   * _.includes([1, 2, 3], 1);
   * // => true
   *
   * _.includes([1, 2, 3], 1, 2);
   * // => false
   *
   * _.includes({ 'a': 1, 'b': 2 }, 1);
   * // => true
   *
   * _.includes('abcd', 'bc');
   * // => true
   */
  function includes(collection, value, fromIndex, guard) {
    collection = isArrayLike(collection) ? collection : values(collection);
    fromIndex = (fromIndex && !guard) ? toInteger(fromIndex) : 0;

    var length = collection.length;
    if (fromIndex < 0) {
      fromIndex = nativeMax(length + fromIndex, 0);
    }
    return isString(collection)
      ? (fromIndex <= length && collection.indexOf(value, fromIndex) > -1)
      : (!!length && baseIndexOf(collection, value, fromIndex) > -1);
  }

  /**
   * Invokes the method at `path` of each element in `collection`, returning
   * an array of the results of each invoked method. Any additional arguments
   * are provided to each invoked method. If `path` is a function, it's invoked
   * for, and `this` bound to, each element in `collection`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Array|Function|string} path The path of the method to invoke or
   *  the function invoked per iteration.
   * @param {...*} [args] The arguments to invoke each method with.
   * @returns {Array} Returns the array of results.
   * @example
   *
   * _.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort');
   * // => [[1, 5, 7], [1, 2, 3]]
   *
   * _.invokeMap([123, 456], String.prototype.split, '');
   * // => [['1', '2', '3'], ['4', '5', '6']]
   */
  var invokeMap = baseRest(function(collection, path, args) {
    var index = -1,
        isFunc = typeof path == 'function',
        result = isArrayLike(collection) ? Array(collection.length) : [];

    baseEach(collection, function(value) {
      result[++index] = isFunc ? apply(path, value, args) : baseInvoke(value, path, args);
    });
    return result;
  });

  /**
   * Creates an object composed of keys generated from the results of running
   * each element of `collection` thru `iteratee`. The corresponding value of
   * each key is the last element responsible for generating the key. The
   * iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
   * @returns {Object} Returns the composed aggregate object.
   * @example
   *
   * var array = [
   *   { 'dir': 'left', 'code': 97 },
   *   { 'dir': 'right', 'code': 100 }
   * ];
   *
   * _.keyBy(array, function(o) {
   *   return String.fromCharCode(o.code);
   * });
   * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
   *
   * _.keyBy(array, 'dir');
   * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
   */
  var keyBy = createAggregator(function(result, value, key) {
    baseAssignValue(result, key, value);
  });

  /**
   * Creates an array of values by running each element in `collection` thru
   * `iteratee`. The iteratee is invoked with three arguments:
   * (value, index|key, collection).
   *
   * Many lodash methods are guarded to work as iteratees for methods like
   * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
   *
   * The guarded methods are:
   * `ary`, `chunk`, `curry`, `curryRight`, `drop`, `dropRight`, `every`,
   * `fill`, `invert`, `parseInt`, `random`, `range`, `rangeRight`, `repeat`,
   * `sampleSize`, `slice`, `some`, `sortBy`, `split`, `take`, `takeRight`,
   * `template`, `trim`, `trimEnd`, `trimStart`, and `words`
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new mapped array.
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * _.map([4, 8], square);
   * // => [16, 64]
   *
   * _.map({ 'a': 4, 'b': 8 }, square);
   * // => [16, 64] (iteration order is not guaranteed)
   *
   * var users = [
   *   { 'user': 'barney' },
   *   { 'user': 'fred' }
   * ];
   *
   * // The `_.property` iteratee shorthand.
   * _.map(users, 'user');
   * // => ['barney', 'fred']
   */
  function map(collection, iteratee) {
    var func = isArray(collection) ? arrayMap : baseMap;
    return func(collection, getIteratee(iteratee, 3));
  }

  /**
   * This method is like `_.sortBy` except that it allows specifying the sort
   * orders of the iteratees to sort by. If `orders` is unspecified, all values
   * are sorted in ascending order. Otherwise, specify an order of "desc" for
   * descending or "asc" for ascending sort order of corresponding values.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Array[]|Function[]|Object[]|string[]} [iteratees=[_.identity]]
   *  The iteratees to sort by.
   * @param {string[]} [orders] The sort orders of `iteratees`.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`.
   * @returns {Array} Returns the new sorted array.
   * @example
   *
   * var users = [
   *   { 'user': 'fred',   'age': 48 },
   *   { 'user': 'barney', 'age': 34 },
   *   { 'user': 'fred',   'age': 40 },
   *   { 'user': 'barney', 'age': 36 }
   * ];
   *
   * // Sort by `user` in ascending order and by `age` in descending order.
   * _.orderBy(users, ['user', 'age'], ['asc', 'desc']);
   * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
   */
  function orderBy(collection, iteratees, orders, guard) {
    if (collection == null) {
      return [];
    }
    if (!isArray(iteratees)) {
      iteratees = iteratees == null ? [] : [iteratees];
    }
    orders = guard ? undefined : orders;
    if (!isArray(orders)) {
      orders = orders == null ? [] : [orders];
    }
    return baseOrderBy(collection, iteratees, orders);
  }

  /**
   * Creates an array of elements split into two groups, the first of which
   * contains elements `predicate` returns truthy for, the second of which
   * contains elements `predicate` returns falsey for. The predicate is
   * invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the array of grouped elements.
   * @example
   *
   * var users = [
   *   { 'user': 'barney',  'age': 36, 'active': false },
   *   { 'user': 'fred',    'age': 40, 'active': true },
   *   { 'user': 'pebbles', 'age': 1,  'active': false }
   * ];
   *
   * _.partition(users, function(o) { return o.active; });
   * // => objects for [['fred'], ['barney', 'pebbles']]
   *
   * // The `_.matches` iteratee shorthand.
   * _.partition(users, { 'age': 1, 'active': false });
   * // => objects for [['pebbles'], ['barney', 'fred']]
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.partition(users, ['active', false]);
   * // => objects for [['barney', 'pebbles'], ['fred']]
   *
   * // The `_.property` iteratee shorthand.
   * _.partition(users, 'active');
   * // => objects for [['fred'], ['barney', 'pebbles']]
   */
  var partition = createAggregator(function(result, value, key) {
    result[key ? 0 : 1].push(value);
  }, function() { return [[], []]; });

  /**
   * Reduces `collection` to a value which is the accumulated result of running
   * each element in `collection` thru `iteratee`, where each successive
   * invocation is supplied the return value of the previous. If `accumulator`
   * is not given, the first element of `collection` is used as the initial
   * value. The iteratee is invoked with four arguments:
   * (accumulator, value, index|key, collection).
   *
   * Many lodash methods are guarded to work as iteratees for methods like
   * `_.reduce`, `_.reduceRight`, and `_.transform`.
   *
   * The guarded methods are:
   * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`,
   * and `sortBy`
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @param {*} [accumulator] The initial value.
   * @returns {*} Returns the accumulated value.
   * @see _.reduceRight
   * @example
   *
   * _.reduce([1, 2], function(sum, n) {
   *   return sum + n;
   * }, 0);
   * // => 3
   *
   * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
   *   (result[value] || (result[value] = [])).push(key);
   *   return result;
   * }, {});
   * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
   */
  function reduce(collection, iteratee, accumulator) {
    var func = isArray(collection) ? arrayReduce : baseReduce,
        initAccum = arguments.length < 3;

    return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEach);
  }

  /**
   * This method is like `_.reduce` except that it iterates over elements of
   * `collection` from right to left.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @param {*} [accumulator] The initial value.
   * @returns {*} Returns the accumulated value.
   * @see _.reduce
   * @example
   *
   * var array = [[0, 1], [2, 3], [4, 5]];
   *
   * _.reduceRight(array, function(flattened, other) {
   *   return flattened.concat(other);
   * }, []);
   * // => [4, 5, 2, 3, 0, 1]
   */
  function reduceRight(collection, iteratee, accumulator) {
    var func = isArray(collection) ? arrayReduceRight : baseReduce,
        initAccum = arguments.length < 3;

    return func(collection, getIteratee(iteratee, 4), accumulator, initAccum, baseEachRight);
  }

  /**
   * The opposite of `_.filter`; this method returns the elements of `collection`
   * that `predicate` does **not** return truthy for.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the new filtered array.
   * @see _.filter
   * @example
   *
   * var users = [
   *   { 'user': 'barney', 'age': 36, 'active': false },
   *   { 'user': 'fred',   'age': 40, 'active': true }
   * ];
   *
   * _.reject(users, function(o) { return !o.active; });
   * // => objects for ['fred']
   *
   * // The `_.matches` iteratee shorthand.
   * _.reject(users, { 'age': 40, 'active': true });
   * // => objects for ['barney']
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.reject(users, ['active', false]);
   * // => objects for ['fred']
   *
   * // The `_.property` iteratee shorthand.
   * _.reject(users, 'active');
   * // => objects for ['barney']
   */
  function reject(collection, predicate) {
    var func = isArray(collection) ? arrayFilter : baseFilter;
    return func(collection, negate(getIteratee(predicate, 3)));
  }

  /**
   * Gets a random element from `collection`.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to sample.
   * @returns {*} Returns the random element.
   * @example
   *
   * _.sample([1, 2, 3, 4]);
   * // => 2
   */
  function sample(collection) {
    var func = isArray(collection) ? arraySample : baseSample;
    return func(collection);
  }

  /**
   * Gets `n` random elements at unique keys from `collection` up to the
   * size of `collection`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Collection
   * @param {Array|Object} collection The collection to sample.
   * @param {number} [n=1] The number of elements to sample.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the random elements.
   * @example
   *
   * _.sampleSize([1, 2, 3], 2);
   * // => [3, 1]
   *
   * _.sampleSize([1, 2, 3], 4);
   * // => [2, 3, 1]
   */
  function sampleSize(collection, n, guard) {
    if ((guard ? isIterateeCall(collection, n, guard) : n === undefined)) {
      n = 1;
    } else {
      n = toInteger(n);
    }
    var func = isArray(collection) ? arraySampleSize : baseSampleSize;
    return func(collection, n);
  }

  /**
   * Creates an array of shuffled values, using a version of the
   * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to shuffle.
   * @returns {Array} Returns the new shuffled array.
   * @example
   *
   * _.shuffle([1, 2, 3, 4]);
   * // => [4, 1, 3, 2]
   */
  function shuffle(collection) {
    var func = isArray(collection) ? arrayShuffle : baseShuffle;
    return func(collection);
  }

  /**
   * Gets the size of `collection` by returning its length for array-like
   * values or the number of own enumerable string keyed properties for objects.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object|string} collection The collection to inspect.
   * @returns {number} Returns the collection size.
   * @example
   *
   * _.size([1, 2, 3]);
   * // => 3
   *
   * _.size({ 'a': 1, 'b': 2 });
   * // => 2
   *
   * _.size('pebbles');
   * // => 7
   */
  function size(collection) {
    if (collection == null) {
      return 0;
    }
    if (isArrayLike(collection)) {
      return isString(collection) ? stringSize(collection) : collection.length;
    }
    var tag = getTag(collection);
    if (tag == mapTag || tag == setTag) {
      return collection.size;
    }
    return baseKeys(collection).length;
  }

  /**
   * Checks if `predicate` returns truthy for **any** element of `collection`.
   * Iteration is stopped once `predicate` returns truthy. The predicate is
   * invoked with three arguments: (value, index|key, collection).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {boolean} Returns `true` if any element passes the predicate check,
   *  else `false`.
   * @example
   *
   * _.some([null, 0, 'yes', false], Boolean);
   * // => true
   *
   * var users = [
   *   { 'user': 'barney', 'active': true },
   *   { 'user': 'fred',   'active': false }
   * ];
   *
   * // The `_.matches` iteratee shorthand.
   * _.some(users, { 'user': 'barney', 'active': false });
   * // => false
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.some(users, ['active', false]);
   * // => true
   *
   * // The `_.property` iteratee shorthand.
   * _.some(users, 'active');
   * // => true
   */
  function some(collection, predicate, guard) {
    var func = isArray(collection) ? arraySome : baseSome;
    if (guard && isIterateeCall(collection, predicate, guard)) {
      predicate = undefined;
    }
    return func(collection, getIteratee(predicate, 3));
  }

  /**
   * Creates an array of elements, sorted in ascending order by the results of
   * running each element in a collection thru each iteratee. This method
   * performs a stable sort, that is, it preserves the original sort order of
   * equal elements. The iteratees are invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Collection
   * @param {Array|Object} collection The collection to iterate over.
   * @param {...(Function|Function[])} [iteratees=[_.identity]]
   *  The iteratees to sort by.
   * @returns {Array} Returns the new sorted array.
   * @example
   *
   * var users = [
   *   { 'user': 'fred',   'age': 48 },
   *   { 'user': 'barney', 'age': 36 },
   *   { 'user': 'fred',   'age': 40 },
   *   { 'user': 'barney', 'age': 34 }
   * ];
   *
   * _.sortBy(users, [function(o) { return o.user; }]);
   * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
   *
   * _.sortBy(users, ['user', 'age']);
   * // => objects for [['barney', 34], ['barney', 36], ['fred', 40], ['fred', 48]]
   */
  var sortBy = baseRest(function(collection, iteratees) {
    if (collection == null) {
      return [];
    }
    var length = iteratees.length;
    if (length > 1 && isIterateeCall(collection, iteratees[0], iteratees[1])) {
      iteratees = [];
    } else if (length > 2 && isIterateeCall(iteratees[0], iteratees[1], iteratees[2])) {
      iteratees = [iteratees[0]];
    }
    return baseOrderBy(collection, baseFlatten(iteratees, 1), []);
  });

  /*------------------------------------------------------------------------*/

  /**
   * Gets the timestamp of the number of milliseconds that have elapsed since
   * the Unix epoch (1 January 1970 00:00:00 UTC).
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Date
   * @returns {number} Returns the timestamp.
   * @example
   *
   * _.defer(function(stamp) {
   *   console.log(_.now() - stamp);
   * }, _.now());
   * // => Logs the number of milliseconds it took for the deferred invocation.
   */
  var now = ctxNow || function() {
    return root.Date.now();
  };

  /*------------------------------------------------------------------------*/

  /**
   * The opposite of `_.before`; this method creates a function that invokes
   * `func` once it's called `n` or more times.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {number} n The number of calls before `func` is invoked.
   * @param {Function} func The function to restrict.
   * @returns {Function} Returns the new restricted function.
   * @example
   *
   * var saves = ['profile', 'settings'];
   *
   * var done = _.after(saves.length, function() {
   *   console.log('done saving!');
   * });
   *
   * _.forEach(saves, function(type) {
   *   asyncSave({ 'type': type, 'complete': done });
   * });
   * // => Logs 'done saving!' after the two async saves have completed.
   */
  function after(n, func) {
    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    n = toInteger(n);
    return function() {
      if (--n < 1) {
        return func.apply(this, arguments);
      }
    };
  }

  /**
   * Creates a function that invokes `func`, with up to `n` arguments,
   * ignoring any additional arguments.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Function
   * @param {Function} func The function to cap arguments for.
   * @param {number} [n=func.length] The arity cap.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Function} Returns the new capped function.
   * @example
   *
   * _.map(['6', '8', '10'], _.ary(parseInt, 1));
   * // => [6, 8, 10]
   */
  function ary(func, n, guard) {
    n = guard ? undefined : n;
    n = (func && n == null) ? func.length : n;
    return createWrap(func, WRAP_ARY_FLAG, undefined, undefined, undefined, undefined, n);
  }

  /**
   * Creates a function that invokes `func`, with the `this` binding and arguments
   * of the created function, while it's called less than `n` times. Subsequent
   * calls to the created function return the result of the last `func` invocation.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Function
   * @param {number} n The number of calls at which `func` is no longer invoked.
   * @param {Function} func The function to restrict.
   * @returns {Function} Returns the new restricted function.
   * @example
   *
   * jQuery(element).on('click', _.before(5, addContactToList));
   * // => Allows adding up to 4 contacts to the list.
   */
  function before(n, func) {
    var result;
    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    n = toInteger(n);
    return function() {
      if (--n > 0) {
        result = func.apply(this, arguments);
      }
      if (n <= 1) {
        func = undefined;
      }
      return result;
    };
  }

  /**
   * Creates a function that invokes `func` with the `this` binding of `thisArg`
   * and `partials` prepended to the arguments it receives.
   *
   * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds,
   * may be used as a placeholder for partially applied arguments.
   *
   * **Note:** Unlike native `Function#bind`, this method doesn't set the "length"
   * property of bound functions.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to bind.
   * @param {*} thisArg The `this` binding of `func`.
   * @param {...*} [partials] The arguments to be partially applied.
   * @returns {Function} Returns the new bound function.
   * @example
   *
   * function greet(greeting, punctuation) {
   *   return greeting + ' ' + this.user + punctuation;
   * }
   *
   * var object = { 'user': 'fred' };
   *
   * var bound = _.bind(greet, object, 'hi');
   * bound('!');
   * // => 'hi fred!'
   *
   * // Bound with placeholders.
   * var bound = _.bind(greet, object, _, '!');
   * bound('hi');
   * // => 'hi fred!'
   */
  var bind = baseRest(function(func, thisArg, partials) {
    var bitmask = WRAP_BIND_FLAG;
    if (partials.length) {
      var holders = replaceHolders(partials, getHolder(bind));
      bitmask |= WRAP_PARTIAL_FLAG;
    }
    return createWrap(func, bitmask, thisArg, partials, holders);
  });

  /**
   * Creates a function that invokes the method at `object[key]` with `partials`
   * prepended to the arguments it receives.
   *
   * This method differs from `_.bind` by allowing bound functions to reference
   * methods that may be redefined or don't yet exist. See
   * [Peter Michaux's article](http://peter.michaux.ca/articles/lazy-function-definition-pattern)
   * for more details.
   *
   * The `_.bindKey.placeholder` value, which defaults to `_` in monolithic
   * builds, may be used as a placeholder for partially applied arguments.
   *
   * @static
   * @memberOf _
   * @since 0.10.0
   * @category Function
   * @param {Object} object The object to invoke the method on.
   * @param {string} key The key of the method.
   * @param {...*} [partials] The arguments to be partially applied.
   * @returns {Function} Returns the new bound function.
   * @example
   *
   * var object = {
   *   'user': 'fred',
   *   'greet': function(greeting, punctuation) {
   *     return greeting + ' ' + this.user + punctuation;
   *   }
   * };
   *
   * var bound = _.bindKey(object, 'greet', 'hi');
   * bound('!');
   * // => 'hi fred!'
   *
   * object.greet = function(greeting, punctuation) {
   *   return greeting + 'ya ' + this.user + punctuation;
   * };
   *
   * bound('!');
   * // => 'hiya fred!'
   *
   * // Bound with placeholders.
   * var bound = _.bindKey(object, 'greet', _, '!');
   * bound('hi');
   * // => 'hiya fred!'
   */
  var bindKey = baseRest(function(object, key, partials) {
    var bitmask = WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG;
    if (partials.length) {
      var holders = replaceHolders(partials, getHolder(bindKey));
      bitmask |= WRAP_PARTIAL_FLAG;
    }
    return createWrap(key, bitmask, object, partials, holders);
  });

  /**
   * Creates a function that accepts arguments of `func` and either invokes
   * `func` returning its result, if at least `arity` number of arguments have
   * been provided, or returns a function that accepts the remaining `func`
   * arguments, and so on. The arity of `func` may be specified if `func.length`
   * is not sufficient.
   *
   * The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
   * may be used as a placeholder for provided arguments.
   *
   * **Note:** This method doesn't set the "length" property of curried functions.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Function
   * @param {Function} func The function to curry.
   * @param {number} [arity=func.length] The arity of `func`.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Function} Returns the new curried function.
   * @example
   *
   * var abc = function(a, b, c) {
   *   return [a, b, c];
   * };
   *
   * var curried = _.curry(abc);
   *
   * curried(1)(2)(3);
   * // => [1, 2, 3]
   *
   * curried(1, 2)(3);
   * // => [1, 2, 3]
   *
   * curried(1, 2, 3);
   * // => [1, 2, 3]
   *
   * // Curried with placeholders.
   * curried(1)(_, 3)(2);
   * // => [1, 2, 3]
   */
  function curry(func, arity, guard) {
    arity = guard ? undefined : arity;
    var result = createWrap(func, WRAP_CURRY_FLAG, undefined, undefined, undefined, undefined, undefined, arity);
    result.placeholder = curry.placeholder;
    return result;
  }

  /**
   * This method is like `_.curry` except that arguments are applied to `func`
   * in the manner of `_.partialRight` instead of `_.partial`.
   *
   * The `_.curryRight.placeholder` value, which defaults to `_` in monolithic
   * builds, may be used as a placeholder for provided arguments.
   *
   * **Note:** This method doesn't set the "length" property of curried functions.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Function
   * @param {Function} func The function to curry.
   * @param {number} [arity=func.length] The arity of `func`.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Function} Returns the new curried function.
   * @example
   *
   * var abc = function(a, b, c) {
   *   return [a, b, c];
   * };
   *
   * var curried = _.curryRight(abc);
   *
   * curried(3)(2)(1);
   * // => [1, 2, 3]
   *
   * curried(2, 3)(1);
   * // => [1, 2, 3]
   *
   * curried(1, 2, 3);
   * // => [1, 2, 3]
   *
   * // Curried with placeholders.
   * curried(3)(1, _)(2);
   * // => [1, 2, 3]
   */
  function curryRight(func, arity, guard) {
    arity = guard ? undefined : arity;
    var result = createWrap(func, WRAP_CURRY_RIGHT_FLAG, undefined, undefined, undefined, undefined, undefined, arity);
    result.placeholder = curryRight.placeholder;
    return result;
  }

  /**
   * Creates a debounced function that delays invoking `func` until after `wait`
   * milliseconds have elapsed since the last time the debounced function was
   * invoked. The debounced function comes with a `cancel` method to cancel
   * delayed `func` invocations and a `flush` method to immediately invoke them.
   * Provide `options` to indicate whether `func` should be invoked on the
   * leading and/or trailing edge of the `wait` timeout. The `func` is invoked
   * with the last arguments provided to the debounced function. Subsequent
   * calls to the debounced function return the result of the last `func`
   * invocation.
   *
   * **Note:** If `leading` and `trailing` options are `true`, `func` is
   * invoked on the trailing edge of the timeout only if the debounced function
   * is invoked more than once during the `wait` timeout.
   *
   * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred
   * until to the next tick, similar to `setTimeout` with a timeout of `0`.
   *
   * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/)
   * for details over the differences between `_.debounce` and `_.throttle`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to debounce.
   * @param {number} [wait=0] The number of milliseconds to delay.
   * @param {Object} [options={}] The options object.
   * @param {boolean} [options.leading=false]
   *  Specify invoking on the leading edge of the timeout.
   * @param {number} [options.maxWait]
   *  The maximum time `func` is allowed to be delayed before it's invoked.
   * @param {boolean} [options.trailing=true]
   *  Specify invoking on the trailing edge of the timeout.
   * @returns {Function} Returns the new debounced function.
   * @example
   *
   * // Avoid costly calculations while the window size is in flux.
   * jQuery(window).on('resize', _.debounce(calculateLayout, 150));
   *
   * // Invoke `sendMail` when clicked, debouncing subsequent calls.
   * jQuery(element).on('click', _.debounce(sendMail, 300, {
   *   'leading': true,
   *   'trailing': false
   * }));
   *
   * // Ensure `batchLog` is invoked once after 1 second of debounced calls.
   * var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 });
   * var source = new EventSource('/stream');
   * jQuery(source).on('message', debounced);
   *
   * // Cancel the trailing debounced invocation.
   * jQuery(window).on('popstate', debounced.cancel);
   */
  function debounce(func, wait, options) {
    var lastArgs,
        lastThis,
        maxWait,
        result,
        timerId,
        lastCallTime,
        lastInvokeTime = 0,
        leading = false,
        maxing = false,
        trailing = true;

    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    wait = toNumber(wait) || 0;
    if (isObject(options)) {
      leading = !!options.leading;
      maxing = 'maxWait' in options;
      maxWait = maxing ? nativeMax(toNumber(options.maxWait) || 0, wait) : maxWait;
      trailing = 'trailing' in options ? !!options.trailing : trailing;
    }

    function invokeFunc(time) {
      var args = lastArgs,
          thisArg = lastThis;

      lastArgs = lastThis = undefined;
      lastInvokeTime = time;
      result = func.apply(thisArg, args);
      return result;
    }

    function leadingEdge(time) {
      // Reset any `maxWait` timer.
      lastInvokeTime = time;
      // Start the timer for the trailing edge.
      timerId = setTimeout(timerExpired, wait);
      // Invoke the leading edge.
      return leading ? invokeFunc(time) : result;
    }

    function remainingWait(time) {
      var timeSinceLastCall = time - lastCallTime,
          timeSinceLastInvoke = time - lastInvokeTime,
          timeWaiting = wait - timeSinceLastCall;

      return maxing
        ? nativeMin(timeWaiting, maxWait - timeSinceLastInvoke)
        : timeWaiting;
    }

    function shouldInvoke(time) {
      var timeSinceLastCall = time - lastCallTime,
          timeSinceLastInvoke = time - lastInvokeTime;

      // Either this is the first call, activity has stopped and we're at the
      // trailing edge, the system time has gone backwards and we're treating
      // it as the trailing edge, or we've hit the `maxWait` limit.
      return (lastCallTime === undefined || (timeSinceLastCall >= wait) ||
        (timeSinceLastCall < 0) || (maxing && timeSinceLastInvoke >= maxWait));
    }

    function timerExpired() {
      var time = now();
      if (shouldInvoke(time)) {
        return trailingEdge(time);
      }
      // Restart the timer.
      timerId = setTimeout(timerExpired, remainingWait(time));
    }

    function trailingEdge(time) {
      timerId = undefined;

      // Only invoke if we have `lastArgs` which means `func` has been
      // debounced at least once.
      if (trailing && lastArgs) {
        return invokeFunc(time);
      }
      lastArgs = lastThis = undefined;
      return result;
    }

    function cancel() {
      if (timerId !== undefined) {
        clearTimeout(timerId);
      }
      lastInvokeTime = 0;
      lastArgs = lastCallTime = lastThis = timerId = undefined;
    }

    function flush() {
      return timerId === undefined ? result : trailingEdge(now());
    }

    function debounced() {
      var time = now(),
          isInvoking = shouldInvoke(time);

      lastArgs = arguments;
      lastThis = this;
      lastCallTime = time;

      if (isInvoking) {
        if (timerId === undefined) {
          return leadingEdge(lastCallTime);
        }
        if (maxing) {
          // Handle invocations in a tight loop.
          clearTimeout(timerId);
          timerId = setTimeout(timerExpired, wait);
          return invokeFunc(lastCallTime);
        }
      }
      if (timerId === undefined) {
        timerId = setTimeout(timerExpired, wait);
      }
      return result;
    }
    debounced.cancel = cancel;
    debounced.flush = flush;
    return debounced;
  }

  /**
   * Defers invoking the `func` until the current call stack has cleared. Any
   * additional arguments are provided to `func` when it's invoked.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to defer.
   * @param {...*} [args] The arguments to invoke `func` with.
   * @returns {number} Returns the timer id.
   * @example
   *
   * _.defer(function(text) {
   *   console.log(text);
   * }, 'deferred');
   * // => Logs 'deferred' after one millisecond.
   */
  var defer = baseRest(function(func, args) {
    return baseDelay(func, 1, args);
  });

  /**
   * Invokes `func` after `wait` milliseconds. Any additional arguments are
   * provided to `func` when it's invoked.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to delay.
   * @param {number} wait The number of milliseconds to delay invocation.
   * @param {...*} [args] The arguments to invoke `func` with.
   * @returns {number} Returns the timer id.
   * @example
   *
   * _.delay(function(text) {
   *   console.log(text);
   * }, 1000, 'later');
   * // => Logs 'later' after one second.
   */
  var delay = baseRest(function(func, wait, args) {
    return baseDelay(func, toNumber(wait) || 0, args);
  });

  /**
   * Creates a function that invokes `func` with arguments reversed.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Function
   * @param {Function} func The function to flip arguments for.
   * @returns {Function} Returns the new flipped function.
   * @example
   *
   * var flipped = _.flip(function() {
   *   return _.toArray(arguments);
   * });
   *
   * flipped('a', 'b', 'c', 'd');
   * // => ['d', 'c', 'b', 'a']
   */
  function flip(func) {
    return createWrap(func, WRAP_FLIP_FLAG);
  }

  /**
   * Creates a function that memoizes the result of `func`. If `resolver` is
   * provided, it determines the cache key for storing the result based on the
   * arguments provided to the memoized function. By default, the first argument
   * provided to the memoized function is used as the map cache key. The `func`
   * is invoked with the `this` binding of the memoized function.
   *
   * **Note:** The cache is exposed as the `cache` property on the memoized
   * function. Its creation may be customized by replacing the `_.memoize.Cache`
   * constructor with one whose instances implement the
   * [`Map`](http://ecma-international.org/ecma-262/7.0/#sec-properties-of-the-map-prototype-object)
   * method interface of `clear`, `delete`, `get`, `has`, and `set`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to have its output memoized.
   * @param {Function} [resolver] The function to resolve the cache key.
   * @returns {Function} Returns the new memoized function.
   * @example
   *
   * var object = { 'a': 1, 'b': 2 };
   * var other = { 'c': 3, 'd': 4 };
   *
   * var values = _.memoize(_.values);
   * values(object);
   * // => [1, 2]
   *
   * values(other);
   * // => [3, 4]
   *
   * object.a = 2;
   * values(object);
   * // => [1, 2]
   *
   * // Modify the result cache.
   * values.cache.set(object, ['a', 'b']);
   * values(object);
   * // => ['a', 'b']
   *
   * // Replace `_.memoize.Cache`.
   * _.memoize.Cache = WeakMap;
   */
  function memoize(func, resolver) {
    if (typeof func != 'function' || (resolver != null && typeof resolver != 'function')) {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    var memoized = function() {
      var args = arguments,
          key = resolver ? resolver.apply(this, args) : args[0],
          cache = memoized.cache;

      if (cache.has(key)) {
        return cache.get(key);
      }
      var result = func.apply(this, args);
      memoized.cache = cache.set(key, result) || cache;
      return result;
    };
    memoized.cache = new (memoize.Cache || MapCache);
    return memoized;
  }

  // Expose `MapCache`.
  memoize.Cache = MapCache;

  /**
   * Creates a function that negates the result of the predicate `func`. The
   * `func` predicate is invoked with the `this` binding and arguments of the
   * created function.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Function
   * @param {Function} predicate The predicate to negate.
   * @returns {Function} Returns the new negated function.
   * @example
   *
   * function isEven(n) {
   *   return n % 2 == 0;
   * }
   *
   * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
   * // => [1, 3, 5]
   */
  function negate(predicate) {
    if (typeof predicate != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    return function() {
      var args = arguments;
      switch (args.length) {
        case 0: return !predicate.call(this);
        case 1: return !predicate.call(this, args[0]);
        case 2: return !predicate.call(this, args[0], args[1]);
        case 3: return !predicate.call(this, args[0], args[1], args[2]);
      }
      return !predicate.apply(this, args);
    };
  }

  /**
   * Creates a function that is restricted to invoking `func` once. Repeat calls
   * to the function return the value of the first invocation. The `func` is
   * invoked with the `this` binding and arguments of the created function.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to restrict.
   * @returns {Function} Returns the new restricted function.
   * @example
   *
   * var initialize = _.once(createApplication);
   * initialize();
   * initialize();
   * // => `createApplication` is invoked once
   */
  function once(func) {
    return before(2, func);
  }

  /**
   * Creates a function that invokes `func` with its arguments transformed.
   *
   * @static
   * @since 4.0.0
   * @memberOf _
   * @category Function
   * @param {Function} func The function to wrap.
   * @param {...(Function|Function[])} [transforms=[_.identity]]
   *  The argument transforms.
   * @returns {Function} Returns the new function.
   * @example
   *
   * function doubled(n) {
   *   return n * 2;
   * }
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var func = _.overArgs(function(x, y) {
   *   return [x, y];
   * }, [square, doubled]);
   *
   * func(9, 3);
   * // => [81, 6]
   *
   * func(10, 5);
   * // => [100, 10]
   */
  var overArgs = castRest(function(func, transforms) {
    transforms = (transforms.length == 1 && isArray(transforms[0]))
      ? arrayMap(transforms[0], baseUnary(getIteratee()))
      : arrayMap(baseFlatten(transforms, 1), baseUnary(getIteratee()));

    var funcsLength = transforms.length;
    return baseRest(function(args) {
      var index = -1,
          length = nativeMin(args.length, funcsLength);

      while (++index < length) {
        args[index] = transforms[index].call(this, args[index]);
      }
      return apply(func, this, args);
    });
  });

  /**
   * Creates a function that invokes `func` with `partials` prepended to the
   * arguments it receives. This method is like `_.bind` except it does **not**
   * alter the `this` binding.
   *
   * The `_.partial.placeholder` value, which defaults to `_` in monolithic
   * builds, may be used as a placeholder for partially applied arguments.
   *
   * **Note:** This method doesn't set the "length" property of partially
   * applied functions.
   *
   * @static
   * @memberOf _
   * @since 0.2.0
   * @category Function
   * @param {Function} func The function to partially apply arguments to.
   * @param {...*} [partials] The arguments to be partially applied.
   * @returns {Function} Returns the new partially applied function.
   * @example
   *
   * function greet(greeting, name) {
   *   return greeting + ' ' + name;
   * }
   *
   * var sayHelloTo = _.partial(greet, 'hello');
   * sayHelloTo('fred');
   * // => 'hello fred'
   *
   * // Partially applied with placeholders.
   * var greetFred = _.partial(greet, _, 'fred');
   * greetFred('hi');
   * // => 'hi fred'
   */
  var partial = baseRest(function(func, partials) {
    var holders = replaceHolders(partials, getHolder(partial));
    return createWrap(func, WRAP_PARTIAL_FLAG, undefined, partials, holders);
  });

  /**
   * This method is like `_.partial` except that partially applied arguments
   * are appended to the arguments it receives.
   *
   * The `_.partialRight.placeholder` value, which defaults to `_` in monolithic
   * builds, may be used as a placeholder for partially applied arguments.
   *
   * **Note:** This method doesn't set the "length" property of partially
   * applied functions.
   *
   * @static
   * @memberOf _
   * @since 1.0.0
   * @category Function
   * @param {Function} func The function to partially apply arguments to.
   * @param {...*} [partials] The arguments to be partially applied.
   * @returns {Function} Returns the new partially applied function.
   * @example
   *
   * function greet(greeting, name) {
   *   return greeting + ' ' + name;
   * }
   *
   * var greetFred = _.partialRight(greet, 'fred');
   * greetFred('hi');
   * // => 'hi fred'
   *
   * // Partially applied with placeholders.
   * var sayHelloTo = _.partialRight(greet, 'hello', _);
   * sayHelloTo('fred');
   * // => 'hello fred'
   */
  var partialRight = baseRest(function(func, partials) {
    var holders = replaceHolders(partials, getHolder(partialRight));
    return createWrap(func, WRAP_PARTIAL_RIGHT_FLAG, undefined, partials, holders);
  });

  /**
   * Creates a function that invokes `func` with arguments arranged according
   * to the specified `indexes` where the argument value at the first index is
   * provided as the first argument, the argument value at the second index is
   * provided as the second argument, and so on.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Function
   * @param {Function} func The function to rearrange arguments for.
   * @param {...(number|number[])} indexes The arranged argument indexes.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var rearged = _.rearg(function(a, b, c) {
   *   return [a, b, c];
   * }, [2, 0, 1]);
   *
   * rearged('b', 'c', 'a')
   * // => ['a', 'b', 'c']
   */
  var rearg = flatRest(function(func, indexes) {
    return createWrap(func, WRAP_REARG_FLAG, undefined, undefined, undefined, indexes);
  });

  /**
   * Creates a function that invokes `func` with the `this` binding of the
   * created function and arguments from `start` and beyond provided as
   * an array.
   *
   * **Note:** This method is based on the
   * [rest parameter](https://mdn.io/rest_parameters).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Function
   * @param {Function} func The function to apply a rest parameter to.
   * @param {number} [start=func.length-1] The start position of the rest parameter.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var say = _.rest(function(what, names) {
   *   return what + ' ' + _.initial(names).join(', ') +
   *     (_.size(names) > 1 ? ', & ' : '') + _.last(names);
   * });
   *
   * say('hello', 'fred', 'barney', 'pebbles');
   * // => 'hello fred, barney, & pebbles'
   */
  function rest(func, start) {
    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    start = start === undefined ? start : toInteger(start);
    return baseRest(func, start);
  }

  /**
   * Creates a function that invokes `func` with the `this` binding of the
   * create function and an array of arguments much like
   * [`Function#apply`](http://www.ecma-international.org/ecma-262/7.0/#sec-function.prototype.apply).
   *
   * **Note:** This method is based on the
   * [spread operator](https://mdn.io/spread_operator).
   *
   * @static
   * @memberOf _
   * @since 3.2.0
   * @category Function
   * @param {Function} func The function to spread arguments over.
   * @param {number} [start=0] The start position of the spread.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var say = _.spread(function(who, what) {
   *   return who + ' says ' + what;
   * });
   *
   * say(['fred', 'hello']);
   * // => 'fred says hello'
   *
   * var numbers = Promise.all([
   *   Promise.resolve(40),
   *   Promise.resolve(36)
   * ]);
   *
   * numbers.then(_.spread(function(x, y) {
   *   return x + y;
   * }));
   * // => a Promise of 76
   */
  function spread(func, start) {
    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    start = start == null ? 0 : nativeMax(toInteger(start), 0);
    return baseRest(function(args) {
      var array = args[start],
          otherArgs = castSlice(args, 0, start);

      if (array) {
        arrayPush(otherArgs, array);
      }
      return apply(func, this, otherArgs);
    });
  }

  /**
   * Creates a throttled function that only invokes `func` at most once per
   * every `wait` milliseconds. The throttled function comes with a `cancel`
   * method to cancel delayed `func` invocations and a `flush` method to
   * immediately invoke them. Provide `options` to indicate whether `func`
   * should be invoked on the leading and/or trailing edge of the `wait`
   * timeout. The `func` is invoked with the last arguments provided to the
   * throttled function. Subsequent calls to the throttled function return the
   * result of the last `func` invocation.
   *
   * **Note:** If `leading` and `trailing` options are `true`, `func` is
   * invoked on the trailing edge of the timeout only if the throttled function
   * is invoked more than once during the `wait` timeout.
   *
   * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred
   * until to the next tick, similar to `setTimeout` with a timeout of `0`.
   *
   * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/)
   * for details over the differences between `_.throttle` and `_.debounce`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to throttle.
   * @param {number} [wait=0] The number of milliseconds to throttle invocations to.
   * @param {Object} [options={}] The options object.
   * @param {boolean} [options.leading=true]
   *  Specify invoking on the leading edge of the timeout.
   * @param {boolean} [options.trailing=true]
   *  Specify invoking on the trailing edge of the timeout.
   * @returns {Function} Returns the new throttled function.
   * @example
   *
   * // Avoid excessively updating the position while scrolling.
   * jQuery(window).on('scroll', _.throttle(updatePosition, 100));
   *
   * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes.
   * var throttled = _.throttle(renewToken, 300000, { 'trailing': false });
   * jQuery(element).on('click', throttled);
   *
   * // Cancel the trailing throttled invocation.
   * jQuery(window).on('popstate', throttled.cancel);
   */
  function throttle(func, wait, options) {
    var leading = true,
        trailing = true;

    if (typeof func != 'function') {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    if (isObject(options)) {
      leading = 'leading' in options ? !!options.leading : leading;
      trailing = 'trailing' in options ? !!options.trailing : trailing;
    }
    return debounce(func, wait, {
      'leading': leading,
      'maxWait': wait,
      'trailing': trailing
    });
  }

  /**
   * Creates a function that accepts up to one argument, ignoring any
   * additional arguments.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Function
   * @param {Function} func The function to cap arguments for.
   * @returns {Function} Returns the new capped function.
   * @example
   *
   * _.map(['6', '8', '10'], _.unary(parseInt));
   * // => [6, 8, 10]
   */
  function unary(func) {
    return ary(func, 1);
  }

  /**
   * Creates a function that provides `value` to `wrapper` as its first
   * argument. Any additional arguments provided to the function are appended
   * to those provided to the `wrapper`. The wrapper is invoked with the `this`
   * binding of the created function.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {*} value The value to wrap.
   * @param {Function} [wrapper=identity] The wrapper function.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var p = _.wrap(_.escape, function(func, text) {
   *   return '<p>' + func(text) + '</p>';
   * });
   *
   * p('fred, barney, & pebbles');
   * // => '<p>fred, barney, &amp; pebbles</p>'
   */
  function wrap(value, wrapper) {
    return partial(castFunction(wrapper), value);
  }

  /*------------------------------------------------------------------------*/

  /**
   * Casts `value` as an array if it's not one.
   *
   * @static
   * @memberOf _
   * @since 4.4.0
   * @category Lang
   * @param {*} value The value to inspect.
   * @returns {Array} Returns the cast array.
   * @example
   *
   * _.castArray(1);
   * // => [1]
   *
   * _.castArray({ 'a': 1 });
   * // => [{ 'a': 1 }]
   *
   * _.castArray('abc');
   * // => ['abc']
   *
   * _.castArray(null);
   * // => [null]
   *
   * _.castArray(undefined);
   * // => [undefined]
   *
   * _.castArray();
   * // => []
   *
   * var array = [1, 2, 3];
   * console.log(_.castArray(array) === array);
   * // => true
   */
  function castArray() {
    if (!arguments.length) {
      return [];
    }
    var value = arguments[0];
    return isArray(value) ? value : [value];
  }

  /**
   * Creates a shallow clone of `value`.
   *
   * **Note:** This method is loosely based on the
   * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm)
   * and supports cloning arrays, array buffers, booleans, date objects, maps,
   * numbers, `Object` objects, regexes, sets, strings, symbols, and typed
   * arrays. The own enumerable properties of `arguments` objects are cloned
   * as plain objects. An empty object is returned for uncloneable values such
   * as error objects, functions, DOM nodes, and WeakMaps.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to clone.
   * @returns {*} Returns the cloned value.
   * @see _.cloneDeep
   * @example
   *
   * var objects = [{ 'a': 1 }, { 'b': 2 }];
   *
   * var shallow = _.clone(objects);
   * console.log(shallow[0] === objects[0]);
   * // => true
   */
  function clone(value) {
    return baseClone(value, CLONE_SYMBOLS_FLAG);
  }

  /**
   * This method is like `_.clone` except that it accepts `customizer` which
   * is invoked to produce the cloned value. If `customizer` returns `undefined`,
   * cloning is handled by the method instead. The `customizer` is invoked with
   * up to four arguments; (value [, index|key, object, stack]).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to clone.
   * @param {Function} [customizer] The function to customize cloning.
   * @returns {*} Returns the cloned value.
   * @see _.cloneDeepWith
   * @example
   *
   * function customizer(value) {
   *   if (_.isElement(value)) {
   *     return value.cloneNode(false);
   *   }
   * }
   *
   * var el = _.cloneWith(document.body, customizer);
   *
   * console.log(el === document.body);
   * // => false
   * console.log(el.nodeName);
   * // => 'BODY'
   * console.log(el.childNodes.length);
   * // => 0
   */
  function cloneWith(value, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    return baseClone(value, CLONE_SYMBOLS_FLAG, customizer);
  }

  /**
   * This method is like `_.clone` except that it recursively clones `value`.
   *
   * @static
   * @memberOf _
   * @since 1.0.0
   * @category Lang
   * @param {*} value The value to recursively clone.
   * @returns {*} Returns the deep cloned value.
   * @see _.clone
   * @example
   *
   * var objects = [{ 'a': 1 }, { 'b': 2 }];
   *
   * var deep = _.cloneDeep(objects);
   * console.log(deep[0] === objects[0]);
   * // => false
   */
  function cloneDeep(value) {
    return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG);
  }

  /**
   * This method is like `_.cloneWith` except that it recursively clones `value`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to recursively clone.
   * @param {Function} [customizer] The function to customize cloning.
   * @returns {*} Returns the deep cloned value.
   * @see _.cloneWith
   * @example
   *
   * function customizer(value) {
   *   if (_.isElement(value)) {
   *     return value.cloneNode(true);
   *   }
   * }
   *
   * var el = _.cloneDeepWith(document.body, customizer);
   *
   * console.log(el === document.body);
   * // => false
   * console.log(el.nodeName);
   * // => 'BODY'
   * console.log(el.childNodes.length);
   * // => 20
   */
  function cloneDeepWith(value, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG, customizer);
  }

  /**
   * Checks if `object` conforms to `source` by invoking the predicate
   * properties of `source` with the corresponding property values of `object`.
   *
   * **Note:** This method is equivalent to `_.conforms` when `source` is
   * partially applied.
   *
   * @static
   * @memberOf _
   * @since 4.14.0
   * @category Lang
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property predicates to conform to.
   * @returns {boolean} Returns `true` if `object` conforms, else `false`.
   * @example
   *
   * var object = { 'a': 1, 'b': 2 };
   *
   * _.conformsTo(object, { 'b': function(n) { return n > 1; } });
   * // => true
   *
   * _.conformsTo(object, { 'b': function(n) { return n > 2; } });
   * // => false
   */
  function conformsTo(object, source) {
    return source == null || baseConformsTo(object, source, keys(source));
  }

  /**
   * Performs a
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * comparison between two values to determine if they are equivalent.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   * @example
   *
   * var object = { 'a': 1 };
   * var other = { 'a': 1 };
   *
   * _.eq(object, object);
   * // => true
   *
   * _.eq(object, other);
   * // => false
   *
   * _.eq('a', 'a');
   * // => true
   *
   * _.eq('a', Object('a'));
   * // => false
   *
   * _.eq(NaN, NaN);
   * // => true
   */
  function eq(value, other) {
    return value === other || (value !== value && other !== other);
  }

  /**
   * Checks if `value` is greater than `other`.
   *
   * @static
   * @memberOf _
   * @since 3.9.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is greater than `other`,
   *  else `false`.
   * @see _.lt
   * @example
   *
   * _.gt(3, 1);
   * // => true
   *
   * _.gt(3, 3);
   * // => false
   *
   * _.gt(1, 3);
   * // => false
   */
  var gt = createRelationalOperation(baseGt);

  /**
   * Checks if `value` is greater than or equal to `other`.
   *
   * @static
   * @memberOf _
   * @since 3.9.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is greater than or equal to
   *  `other`, else `false`.
   * @see _.lte
   * @example
   *
   * _.gte(3, 1);
   * // => true
   *
   * _.gte(3, 3);
   * // => true
   *
   * _.gte(1, 3);
   * // => false
   */
  var gte = createRelationalOperation(function(value, other) {
    return value >= other;
  });

  /**
   * Checks if `value` is likely an `arguments` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an `arguments` object,
   *  else `false`.
   * @example
   *
   * _.isArguments(function() { return arguments; }());
   * // => true
   *
   * _.isArguments([1, 2, 3]);
   * // => false
   */
  var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) {
    return isObjectLike(value) && hasOwnProperty.call(value, 'callee') &&
      !propertyIsEnumerable.call(value, 'callee');
  };

  /**
   * Checks if `value` is classified as an `Array` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array, else `false`.
   * @example
   *
   * _.isArray([1, 2, 3]);
   * // => true
   *
   * _.isArray(document.body.children);
   * // => false
   *
   * _.isArray('abc');
   * // => false
   *
   * _.isArray(_.noop);
   * // => false
   */
  var isArray = Array.isArray;

  /**
   * Checks if `value` is classified as an `ArrayBuffer` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.
   * @example
   *
   * _.isArrayBuffer(new ArrayBuffer(2));
   * // => true
   *
   * _.isArrayBuffer(new Array(2));
   * // => false
   */
  var isArrayBuffer = nodeIsArrayBuffer ? baseUnary(nodeIsArrayBuffer) : baseIsArrayBuffer;

  /**
   * Checks if `value` is array-like. A value is considered array-like if it's
   * not a function and has a `value.length` that's an integer greater than or
   * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is array-like, else `false`.
   * @example
   *
   * _.isArrayLike([1, 2, 3]);
   * // => true
   *
   * _.isArrayLike(document.body.children);
   * // => true
   *
   * _.isArrayLike('abc');
   * // => true
   *
   * _.isArrayLike(_.noop);
   * // => false
   */
  function isArrayLike(value) {
    return value != null && isLength(value.length) && !isFunction(value);
  }

  /**
   * This method is like `_.isArrayLike` except that it also checks if `value`
   * is an object.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array-like object,
   *  else `false`.
   * @example
   *
   * _.isArrayLikeObject([1, 2, 3]);
   * // => true
   *
   * _.isArrayLikeObject(document.body.children);
   * // => true
   *
   * _.isArrayLikeObject('abc');
   * // => false
   *
   * _.isArrayLikeObject(_.noop);
   * // => false
   */
  function isArrayLikeObject(value) {
    return isObjectLike(value) && isArrayLike(value);
  }

  /**
   * Checks if `value` is classified as a boolean primitive or object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a boolean, else `false`.
   * @example
   *
   * _.isBoolean(false);
   * // => true
   *
   * _.isBoolean(null);
   * // => false
   */
  function isBoolean(value) {
    return value === true || value === false ||
      (isObjectLike(value) && baseGetTag(value) == boolTag);
  }

  /**
   * Checks if `value` is a buffer.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a buffer, else `false`.
   * @example
   *
   * _.isBuffer(new Buffer(2));
   * // => true
   *
   * _.isBuffer(new Uint8Array(2));
   * // => false
   */
  var isBuffer = nativeIsBuffer || stubFalse;

  /**
   * Checks if `value` is classified as a `Date` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a date object, else `false`.
   * @example
   *
   * _.isDate(new Date);
   * // => true
   *
   * _.isDate('Mon April 23 2012');
   * // => false
   */
  var isDate = nodeIsDate ? baseUnary(nodeIsDate) : baseIsDate;

  /**
   * Checks if `value` is likely a DOM element.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a DOM element, else `false`.
   * @example
   *
   * _.isElement(document.body);
   * // => true
   *
   * _.isElement('<body>');
   * // => false
   */
  function isElement(value) {
    return isObjectLike(value) && value.nodeType === 1 && !isPlainObject(value);
  }

  /**
   * Checks if `value` is an empty object, collection, map, or set.
   *
   * Objects are considered empty if they have no own enumerable string keyed
   * properties.
   *
   * Array-like values such as `arguments` objects, arrays, buffers, strings, or
   * jQuery-like collections are considered empty if they have a `length` of `0`.
   * Similarly, maps and sets are considered empty if they have a `size` of `0`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is empty, else `false`.
   * @example
   *
   * _.isEmpty(null);
   * // => true
   *
   * _.isEmpty(true);
   * // => true
   *
   * _.isEmpty(1);
   * // => true
   *
   * _.isEmpty([1, 2, 3]);
   * // => false
   *
   * _.isEmpty({ 'a': 1 });
   * // => false
   */
  function isEmpty(value) {
    if (value == null) {
      return true;
    }
    if (isArrayLike(value) &&
        (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' ||
          isBuffer(value) || isTypedArray(value) || isArguments(value))) {
      return !value.length;
    }
    var tag = getTag(value);
    if (tag == mapTag || tag == setTag) {
      return !value.size;
    }
    if (isPrototype(value)) {
      return !baseKeys(value).length;
    }
    for (var key in value) {
      if (hasOwnProperty.call(value, key)) {
        return false;
      }
    }
    return true;
  }

  /**
   * Performs a deep comparison between two values to determine if they are
   * equivalent.
   *
   * **Note:** This method supports comparing arrays, array buffers, booleans,
   * date objects, error objects, maps, numbers, `Object` objects, regexes,
   * sets, strings, symbols, and typed arrays. `Object` objects are compared
   * by their own, not inherited, enumerable properties. Functions and DOM
   * nodes are compared by strict equality, i.e. `===`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   * @example
   *
   * var object = { 'a': 1 };
   * var other = { 'a': 1 };
   *
   * _.isEqual(object, other);
   * // => true
   *
   * object === other;
   * // => false
   */
  function isEqual(value, other) {
    return baseIsEqual(value, other);
  }

  /**
   * This method is like `_.isEqual` except that it accepts `customizer` which
   * is invoked to compare values. If `customizer` returns `undefined`, comparisons
   * are handled by the method instead. The `customizer` is invoked with up to
   * six arguments: (objValue, othValue [, index|key, object, other, stack]).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @param {Function} [customizer] The function to customize comparisons.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   * @example
   *
   * function isGreeting(value) {
   *   return /^h(?:i|ello)$/.test(value);
   * }
   *
   * function customizer(objValue, othValue) {
   *   if (isGreeting(objValue) && isGreeting(othValue)) {
   *     return true;
   *   }
   * }
   *
   * var array = ['hello', 'goodbye'];
   * var other = ['hi', 'goodbye'];
   *
   * _.isEqualWith(array, other, customizer);
   * // => true
   */
  function isEqualWith(value, other, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    var result = customizer ? customizer(value, other) : undefined;
    return result === undefined ? baseIsEqual(value, other, undefined, customizer) : !!result;
  }

  /**
   * Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`,
   * `SyntaxError`, `TypeError`, or `URIError` object.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an error object, else `false`.
   * @example
   *
   * _.isError(new Error);
   * // => true
   *
   * _.isError(Error);
   * // => false
   */
  function isError(value) {
    if (!isObjectLike(value)) {
      return false;
    }
    var tag = baseGetTag(value);
    return tag == errorTag || tag == domExcTag ||
      (typeof value.message == 'string' && typeof value.name == 'string' && !isPlainObject(value));
  }

  /**
   * Checks if `value` is a finite primitive number.
   *
   * **Note:** This method is based on
   * [`Number.isFinite`](https://mdn.io/Number/isFinite).
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a finite number, else `false`.
   * @example
   *
   * _.isFinite(3);
   * // => true
   *
   * _.isFinite(Number.MIN_VALUE);
   * // => true
   *
   * _.isFinite(Infinity);
   * // => false
   *
   * _.isFinite('3');
   * // => false
   */
  function isFinite(value) {
    return typeof value == 'number' && nativeIsFinite(value);
  }

  /**
   * Checks if `value` is classified as a `Function` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a function, else `false`.
   * @example
   *
   * _.isFunction(_);
   * // => true
   *
   * _.isFunction(/abc/);
   * // => false
   */
  function isFunction(value) {
    if (!isObject(value)) {
      return false;
    }
    // The use of `Object#toString` avoids issues with the `typeof` operator
    // in Safari 9 which returns 'object' for typed arrays and other constructors.
    var tag = baseGetTag(value);
    return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag;
  }

  /**
   * Checks if `value` is an integer.
   *
   * **Note:** This method is based on
   * [`Number.isInteger`](https://mdn.io/Number/isInteger).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an integer, else `false`.
   * @example
   *
   * _.isInteger(3);
   * // => true
   *
   * _.isInteger(Number.MIN_VALUE);
   * // => false
   *
   * _.isInteger(Infinity);
   * // => false
   *
   * _.isInteger('3');
   * // => false
   */
  function isInteger(value) {
    return typeof value == 'number' && value == toInteger(value);
  }

  /**
   * Checks if `value` is a valid array-like length.
   *
   * **Note:** This method is loosely based on
   * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
   * @example
   *
   * _.isLength(3);
   * // => true
   *
   * _.isLength(Number.MIN_VALUE);
   * // => false
   *
   * _.isLength(Infinity);
   * // => false
   *
   * _.isLength('3');
   * // => false
   */
  function isLength(value) {
    return typeof value == 'number' &&
      value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
  }

  /**
   * Checks if `value` is the
   * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
   * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an object, else `false`.
   * @example
   *
   * _.isObject({});
   * // => true
   *
   * _.isObject([1, 2, 3]);
   * // => true
   *
   * _.isObject(_.noop);
   * // => true
   *
   * _.isObject(null);
   * // => false
   */
  function isObject(value) {
    var type = typeof value;
    return value != null && (type == 'object' || type == 'function');
  }

  /**
   * Checks if `value` is object-like. A value is object-like if it's not `null`
   * and has a `typeof` result of "object".
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
   * @example
   *
   * _.isObjectLike({});
   * // => true
   *
   * _.isObjectLike([1, 2, 3]);
   * // => true
   *
   * _.isObjectLike(_.noop);
   * // => false
   *
   * _.isObjectLike(null);
   * // => false
   */
  function isObjectLike(value) {
    return value != null && typeof value == 'object';
  }

  /**
   * Checks if `value` is classified as a `Map` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a map, else `false`.
   * @example
   *
   * _.isMap(new Map);
   * // => true
   *
   * _.isMap(new WeakMap);
   * // => false
   */
  var isMap = nodeIsMap ? baseUnary(nodeIsMap) : baseIsMap;

  /**
   * Performs a partial deep comparison between `object` and `source` to
   * determine if `object` contains equivalent property values.
   *
   * **Note:** This method is equivalent to `_.matches` when `source` is
   * partially applied.
   *
   * Partial comparisons will match empty array and empty object `source`
   * values against any array or object value, respectively. See `_.isEqual`
   * for a list of supported value comparisons.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property values to match.
   * @returns {boolean} Returns `true` if `object` is a match, else `false`.
   * @example
   *
   * var object = { 'a': 1, 'b': 2 };
   *
   * _.isMatch(object, { 'b': 2 });
   * // => true
   *
   * _.isMatch(object, { 'b': 1 });
   * // => false
   */
  function isMatch(object, source) {
    return object === source || baseIsMatch(object, source, getMatchData(source));
  }

  /**
   * This method is like `_.isMatch` except that it accepts `customizer` which
   * is invoked to compare values. If `customizer` returns `undefined`, comparisons
   * are handled by the method instead. The `customizer` is invoked with five
   * arguments: (objValue, srcValue, index|key, object, source).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property values to match.
   * @param {Function} [customizer] The function to customize comparisons.
   * @returns {boolean} Returns `true` if `object` is a match, else `false`.
   * @example
   *
   * function isGreeting(value) {
   *   return /^h(?:i|ello)$/.test(value);
   * }
   *
   * function customizer(objValue, srcValue) {
   *   if (isGreeting(objValue) && isGreeting(srcValue)) {
   *     return true;
   *   }
   * }
   *
   * var object = { 'greeting': 'hello' };
   * var source = { 'greeting': 'hi' };
   *
   * _.isMatchWith(object, source, customizer);
   * // => true
   */
  function isMatchWith(object, source, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    return baseIsMatch(object, source, getMatchData(source), customizer);
  }

  /**
   * Checks if `value` is `NaN`.
   *
   * **Note:** This method is based on
   * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as
   * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for
   * `undefined` and other non-number values.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
   * @example
   *
   * _.isNaN(NaN);
   * // => true
   *
   * _.isNaN(new Number(NaN));
   * // => true
   *
   * isNaN(undefined);
   * // => true
   *
   * _.isNaN(undefined);
   * // => false
   */
  function isNaN(value) {
    // An `NaN` primitive is the only value that is not equal to itself.
    // Perform the `toStringTag` check first to avoid errors with some
    // ActiveX objects in IE.
    return isNumber(value) && value != +value;
  }

  /**
   * Checks if `value` is a pristine native function.
   *
   * **Note:** This method can't reliably detect native functions in the presence
   * of the core-js package because core-js circumvents this kind of detection.
   * Despite multiple requests, the core-js maintainer has made it clear: any
   * attempt to fix the detection will be obstructed. As a result, we're left
   * with little choice but to throw an error. Unfortunately, this also affects
   * packages, like [babel-polyfill](https://www.npmjs.com/package/babel-polyfill),
   * which rely on core-js.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a native function,
   *  else `false`.
   * @example
   *
   * _.isNative(Array.prototype.push);
   * // => true
   *
   * _.isNative(_);
   * // => false
   */
  function isNative(value) {
    if (isMaskable(value)) {
      throw new Error(CORE_ERROR_TEXT);
    }
    return baseIsNative(value);
  }

  /**
   * Checks if `value` is `null`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is `null`, else `false`.
   * @example
   *
   * _.isNull(null);
   * // => true
   *
   * _.isNull(void 0);
   * // => false
   */
  function isNull(value) {
    return value === null;
  }

  /**
   * Checks if `value` is `null` or `undefined`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is nullish, else `false`.
   * @example
   *
   * _.isNil(null);
   * // => true
   *
   * _.isNil(void 0);
   * // => true
   *
   * _.isNil(NaN);
   * // => false
   */
  function isNil(value) {
    return value == null;
  }

  /**
   * Checks if `value` is classified as a `Number` primitive or object.
   *
   * **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are
   * classified as numbers, use the `_.isFinite` method.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a number, else `false`.
   * @example
   *
   * _.isNumber(3);
   * // => true
   *
   * _.isNumber(Number.MIN_VALUE);
   * // => true
   *
   * _.isNumber(Infinity);
   * // => true
   *
   * _.isNumber('3');
   * // => false
   */
  function isNumber(value) {
    return typeof value == 'number' ||
      (isObjectLike(value) && baseGetTag(value) == numberTag);
  }

  /**
   * Checks if `value` is a plain object, that is, an object created by the
   * `Object` constructor or one with a `[[Prototype]]` of `null`.
   *
   * @static
   * @memberOf _
   * @since 0.8.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   * }
   *
   * _.isPlainObject(new Foo);
   * // => false
   *
   * _.isPlainObject([1, 2, 3]);
   * // => false
   *
   * _.isPlainObject({ 'x': 0, 'y': 0 });
   * // => true
   *
   * _.isPlainObject(Object.create(null));
   * // => true
   */
  function isPlainObject(value) {
    if (!isObjectLike(value) || baseGetTag(value) != objectTag) {
      return false;
    }
    var proto = getPrototype(value);
    if (proto === null) {
      return true;
    }
    var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;
    return typeof Ctor == 'function' && Ctor instanceof Ctor &&
      funcToString.call(Ctor) == objectCtorString;
  }

  /**
   * Checks if `value` is classified as a `RegExp` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
   * @example
   *
   * _.isRegExp(/abc/);
   * // => true
   *
   * _.isRegExp('/abc/');
   * // => false
   */
  var isRegExp = nodeIsRegExp ? baseUnary(nodeIsRegExp) : baseIsRegExp;

  /**
   * Checks if `value` is a safe integer. An integer is safe if it's an IEEE-754
   * double precision number which isn't the result of a rounded unsafe integer.
   *
   * **Note:** This method is based on
   * [`Number.isSafeInteger`](https://mdn.io/Number/isSafeInteger).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a safe integer, else `false`.
   * @example
   *
   * _.isSafeInteger(3);
   * // => true
   *
   * _.isSafeInteger(Number.MIN_VALUE);
   * // => false
   *
   * _.isSafeInteger(Infinity);
   * // => false
   *
   * _.isSafeInteger('3');
   * // => false
   */
  function isSafeInteger(value) {
    return isInteger(value) && value >= -MAX_SAFE_INTEGER && value <= MAX_SAFE_INTEGER;
  }

  /**
   * Checks if `value` is classified as a `Set` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a set, else `false`.
   * @example
   *
   * _.isSet(new Set);
   * // => true
   *
   * _.isSet(new WeakSet);
   * // => false
   */
  var isSet = nodeIsSet ? baseUnary(nodeIsSet) : baseIsSet;

  /**
   * Checks if `value` is classified as a `String` primitive or object.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a string, else `false`.
   * @example
   *
   * _.isString('abc');
   * // => true
   *
   * _.isString(1);
   * // => false
   */
  function isString(value) {
    return typeof value == 'string' ||
      (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag);
  }

  /**
   * Checks if `value` is classified as a `Symbol` primitive or object.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
   * @example
   *
   * _.isSymbol(Symbol.iterator);
   * // => true
   *
   * _.isSymbol('abc');
   * // => false
   */
  function isSymbol(value) {
    return typeof value == 'symbol' ||
      (isObjectLike(value) && baseGetTag(value) == symbolTag);
  }

  /**
   * Checks if `value` is classified as a typed array.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
   * @example
   *
   * _.isTypedArray(new Uint8Array);
   * // => true
   *
   * _.isTypedArray([]);
   * // => false
   */
  var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray;

  /**
   * Checks if `value` is `undefined`.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is `undefined`, else `false`.
   * @example
   *
   * _.isUndefined(void 0);
   * // => true
   *
   * _.isUndefined(null);
   * // => false
   */
  function isUndefined(value) {
    return value === undefined;
  }

  /**
   * Checks if `value` is classified as a `WeakMap` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a weak map, else `false`.
   * @example
   *
   * _.isWeakMap(new WeakMap);
   * // => true
   *
   * _.isWeakMap(new Map);
   * // => false
   */
  function isWeakMap(value) {
    return isObjectLike(value) && getTag(value) == weakMapTag;
  }

  /**
   * Checks if `value` is classified as a `WeakSet` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a weak set, else `false`.
   * @example
   *
   * _.isWeakSet(new WeakSet);
   * // => true
   *
   * _.isWeakSet(new Set);
   * // => false
   */
  function isWeakSet(value) {
    return isObjectLike(value) && baseGetTag(value) == weakSetTag;
  }

  /**
   * Checks if `value` is less than `other`.
   *
   * @static
   * @memberOf _
   * @since 3.9.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is less than `other`,
   *  else `false`.
   * @see _.gt
   * @example
   *
   * _.lt(1, 3);
   * // => true
   *
   * _.lt(3, 3);
   * // => false
   *
   * _.lt(3, 1);
   * // => false
   */
  var lt = createRelationalOperation(baseLt);

  /**
   * Checks if `value` is less than or equal to `other`.
   *
   * @static
   * @memberOf _
   * @since 3.9.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if `value` is less than or equal to
   *  `other`, else `false`.
   * @see _.gte
   * @example
   *
   * _.lte(1, 3);
   * // => true
   *
   * _.lte(3, 3);
   * // => true
   *
   * _.lte(3, 1);
   * // => false
   */
  var lte = createRelationalOperation(function(value, other) {
    return value <= other;
  });

  /**
   * Converts `value` to an array.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {Array} Returns the converted array.
   * @example
   *
   * _.toArray({ 'a': 1, 'b': 2 });
   * // => [1, 2]
   *
   * _.toArray('abc');
   * // => ['a', 'b', 'c']
   *
   * _.toArray(1);
   * // => []
   *
   * _.toArray(null);
   * // => []
   */
  function toArray(value) {
    if (!value) {
      return [];
    }
    if (isArrayLike(value)) {
      return isString(value) ? stringToArray(value) : copyArray(value);
    }
    if (symIterator && value[symIterator]) {
      return iteratorToArray(value[symIterator]());
    }
    var tag = getTag(value),
        func = tag == mapTag ? mapToArray : (tag == setTag ? setToArray : values);

    return func(value);
  }

  /**
   * Converts `value` to a finite number.
   *
   * @static
   * @memberOf _
   * @since 4.12.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {number} Returns the converted number.
   * @example
   *
   * _.toFinite(3.2);
   * // => 3.2
   *
   * _.toFinite(Number.MIN_VALUE);
   * // => 5e-324
   *
   * _.toFinite(Infinity);
   * // => 1.7976931348623157e+308
   *
   * _.toFinite('3.2');
   * // => 3.2
   */
  function toFinite(value) {
    if (!value) {
      return value === 0 ? value : 0;
    }
    value = toNumber(value);
    if (value === INFINITY || value === -INFINITY) {
      var sign = (value < 0 ? -1 : 1);
      return sign * MAX_INTEGER;
    }
    return value === value ? value : 0;
  }

  /**
   * Converts `value` to an integer.
   *
   * **Note:** This method is loosely based on
   * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {number} Returns the converted integer.
   * @example
   *
   * _.toInteger(3.2);
   * // => 3
   *
   * _.toInteger(Number.MIN_VALUE);
   * // => 0
   *
   * _.toInteger(Infinity);
   * // => 1.7976931348623157e+308
   *
   * _.toInteger('3.2');
   * // => 3
   */
  function toInteger(value) {
    var result = toFinite(value),
        remainder = result % 1;

    return result === result ? (remainder ? result - remainder : result) : 0;
  }

  /**
   * Converts `value` to an integer suitable for use as the length of an
   * array-like object.
   *
   * **Note:** This method is based on
   * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {number} Returns the converted integer.
   * @example
   *
   * _.toLength(3.2);
   * // => 3
   *
   * _.toLength(Number.MIN_VALUE);
   * // => 0
   *
   * _.toLength(Infinity);
   * // => 4294967295
   *
   * _.toLength('3.2');
   * // => 3
   */
  function toLength(value) {
    return value ? baseClamp(toInteger(value), 0, MAX_ARRAY_LENGTH) : 0;
  }

  /**
   * Converts `value` to a number.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to process.
   * @returns {number} Returns the number.
   * @example
   *
   * _.toNumber(3.2);
   * // => 3.2
   *
   * _.toNumber(Number.MIN_VALUE);
   * // => 5e-324
   *
   * _.toNumber(Infinity);
   * // => Infinity
   *
   * _.toNumber('3.2');
   * // => 3.2
   */
  function toNumber(value) {
    if (typeof value == 'number') {
      return value;
    }
    if (isSymbol(value)) {
      return NAN;
    }
    if (isObject(value)) {
      var other = typeof value.valueOf == 'function' ? value.valueOf() : value;
      value = isObject(other) ? (other + '') : other;
    }
    if (typeof value != 'string') {
      return value === 0 ? value : +value;
    }
    value = value.replace(reTrim, '');
    var isBinary = reIsBinary.test(value);
    return (isBinary || reIsOctal.test(value))
      ? freeParseInt(value.slice(2), isBinary ? 2 : 8)
      : (reIsBadHex.test(value) ? NAN : +value);
  }

  /**
   * Converts `value` to a plain object flattening inherited enumerable string
   * keyed properties of `value` to own properties of the plain object.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {Object} Returns the converted plain object.
   * @example
   *
   * function Foo() {
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.assign({ 'a': 1 }, new Foo);
   * // => { 'a': 1, 'b': 2 }
   *
   * _.assign({ 'a': 1 }, _.toPlainObject(new Foo));
   * // => { 'a': 1, 'b': 2, 'c': 3 }
   */
  function toPlainObject(value) {
    return copyObject(value, keysIn(value));
  }

  /**
   * Converts `value` to a safe integer. A safe integer can be compared and
   * represented correctly.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {number} Returns the converted integer.
   * @example
   *
   * _.toSafeInteger(3.2);
   * // => 3
   *
   * _.toSafeInteger(Number.MIN_VALUE);
   * // => 0
   *
   * _.toSafeInteger(Infinity);
   * // => 9007199254740991
   *
   * _.toSafeInteger('3.2');
   * // => 3
   */
  function toSafeInteger(value) {
    return value
      ? baseClamp(toInteger(value), -MAX_SAFE_INTEGER, MAX_SAFE_INTEGER)
      : (value === 0 ? value : 0);
  }

  /**
   * Converts `value` to a string. An empty string is returned for `null`
   * and `undefined` values. The sign of `-0` is preserved.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {string} Returns the converted string.
   * @example
   *
   * _.toString(null);
   * // => ''
   *
   * _.toString(-0);
   * // => '-0'
   *
   * _.toString([1, 2, 3]);
   * // => '1,2,3'
   */
  function toString(value) {
    return value == null ? '' : baseToString(value);
  }

  /*------------------------------------------------------------------------*/

  /**
   * Assigns own enumerable string keyed properties of source objects to the
   * destination object. Source objects are applied from left to right.
   * Subsequent sources overwrite property assignments of previous sources.
   *
   * **Note:** This method mutates `object` and is loosely based on
   * [`Object.assign`](https://mdn.io/Object/assign).
   *
   * @static
   * @memberOf _
   * @since 0.10.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @see _.assignIn
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   * }
   *
   * function Bar() {
   *   this.c = 3;
   * }
   *
   * Foo.prototype.b = 2;
   * Bar.prototype.d = 4;
   *
   * _.assign({ 'a': 0 }, new Foo, new Bar);
   * // => { 'a': 1, 'c': 3 }
   */
  var assign = createAssigner(function(object, source) {
    if (isPrototype(source) || isArrayLike(source)) {
      copyObject(source, keys(source), object);
      return;
    }
    for (var key in source) {
      if (hasOwnProperty.call(source, key)) {
        assignValue(object, key, source[key]);
      }
    }
  });

  /**
   * This method is like `_.assign` except that it iterates over own and
   * inherited source properties.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @alias extend
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @see _.assign
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   * }
   *
   * function Bar() {
   *   this.c = 3;
   * }
   *
   * Foo.prototype.b = 2;
   * Bar.prototype.d = 4;
   *
   * _.assignIn({ 'a': 0 }, new Foo, new Bar);
   * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
   */
  var assignIn = createAssigner(function(object, source) {
    copyObject(source, keysIn(source), object);
  });

  /**
   * This method is like `_.assignIn` except that it accepts `customizer`
   * which is invoked to produce the assigned values. If `customizer` returns
   * `undefined`, assignment is handled by the method instead. The `customizer`
   * is invoked with five arguments: (objValue, srcValue, key, object, source).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @alias extendWith
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} sources The source objects.
   * @param {Function} [customizer] The function to customize assigned values.
   * @returns {Object} Returns `object`.
   * @see _.assignWith
   * @example
   *
   * function customizer(objValue, srcValue) {
   *   return _.isUndefined(objValue) ? srcValue : objValue;
   * }
   *
   * var defaults = _.partialRight(_.assignInWith, customizer);
   *
   * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
   * // => { 'a': 1, 'b': 2 }
   */
  var assignInWith = createAssigner(function(object, source, srcIndex, customizer) {
    copyObject(source, keysIn(source), object, customizer);
  });

  /**
   * This method is like `_.assign` except that it accepts `customizer`
   * which is invoked to produce the assigned values. If `customizer` returns
   * `undefined`, assignment is handled by the method instead. The `customizer`
   * is invoked with five arguments: (objValue, srcValue, key, object, source).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} sources The source objects.
   * @param {Function} [customizer] The function to customize assigned values.
   * @returns {Object} Returns `object`.
   * @see _.assignInWith
   * @example
   *
   * function customizer(objValue, srcValue) {
   *   return _.isUndefined(objValue) ? srcValue : objValue;
   * }
   *
   * var defaults = _.partialRight(_.assignWith, customizer);
   *
   * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
   * // => { 'a': 1, 'b': 2 }
   */
  var assignWith = createAssigner(function(object, source, srcIndex, customizer) {
    copyObject(source, keys(source), object, customizer);
  });

  /**
   * Creates an array of values corresponding to `paths` of `object`.
   *
   * @static
   * @memberOf _
   * @since 1.0.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {...(string|string[])} [paths] The property paths to pick.
   * @returns {Array} Returns the picked values.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
   *
   * _.at(object, ['a[0].b.c', 'a[1]']);
   * // => [3, 4]
   */
  var at = flatRest(baseAt);

  /**
   * Creates an object that inherits from the `prototype` object. If a
   * `properties` object is given, its own enumerable string keyed properties
   * are assigned to the created object.
   *
   * @static
   * @memberOf _
   * @since 2.3.0
   * @category Object
   * @param {Object} prototype The object to inherit from.
   * @param {Object} [properties] The properties to assign to the object.
   * @returns {Object} Returns the new object.
   * @example
   *
   * function Shape() {
   *   this.x = 0;
   *   this.y = 0;
   * }
   *
   * function Circle() {
   *   Shape.call(this);
   * }
   *
   * Circle.prototype = _.create(Shape.prototype, {
   *   'constructor': Circle
   * });
   *
   * var circle = new Circle;
   * circle instanceof Circle;
   * // => true
   *
   * circle instanceof Shape;
   * // => true
   */
  function create(prototype, properties) {
    var result = baseCreate(prototype);
    return properties == null ? result : baseAssign(result, properties);
  }

  /**
   * Assigns own and inherited enumerable string keyed properties of source
   * objects to the destination object for all destination properties that
   * resolve to `undefined`. Source objects are applied from left to right.
   * Once a property is set, additional values of the same property are ignored.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @see _.defaultsDeep
   * @example
   *
   * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
   * // => { 'a': 1, 'b': 2 }
   */
  var defaults = baseRest(function(object, sources) {
    object = Object(object);

    var index = -1;
    var length = sources.length;
    var guard = length > 2 ? sources[2] : undefined;

    if (guard && isIterateeCall(sources[0], sources[1], guard)) {
      length = 1;
    }

    while (++index < length) {
      var source = sources[index];
      var props = keysIn(source);
      var propsIndex = -1;
      var propsLength = props.length;

      while (++propsIndex < propsLength) {
        var key = props[propsIndex];
        var value = object[key];

        if (value === undefined ||
            (eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) {
          object[key] = source[key];
        }
      }
    }

    return object;
  });

  /**
   * This method is like `_.defaults` except that it recursively assigns
   * default properties.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 3.10.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @see _.defaults
   * @example
   *
   * _.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } });
   * // => { 'a': { 'b': 2, 'c': 3 } }
   */
  var defaultsDeep = baseRest(function(args) {
    args.push(undefined, customDefaultsMerge);
    return apply(mergeWith, undefined, args);
  });

  /**
   * This method is like `_.find` except that it returns the key of the first
   * element `predicate` returns truthy for instead of the element itself.
   *
   * @static
   * @memberOf _
   * @since 1.1.0
   * @category Object
   * @param {Object} object The object to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {string|undefined} Returns the key of the matched element,
   *  else `undefined`.
   * @example
   *
   * var users = {
   *   'barney':  { 'age': 36, 'active': true },
   *   'fred':    { 'age': 40, 'active': false },
   *   'pebbles': { 'age': 1,  'active': true }
   * };
   *
   * _.findKey(users, function(o) { return o.age < 40; });
   * // => 'barney' (iteration order is not guaranteed)
   *
   * // The `_.matches` iteratee shorthand.
   * _.findKey(users, { 'age': 1, 'active': true });
   * // => 'pebbles'
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.findKey(users, ['active', false]);
   * // => 'fred'
   *
   * // The `_.property` iteratee shorthand.
   * _.findKey(users, 'active');
   * // => 'barney'
   */
  function findKey(object, predicate) {
    return baseFindKey(object, getIteratee(predicate, 3), baseForOwn);
  }

  /**
   * This method is like `_.findKey` except that it iterates over elements of
   * a collection in the opposite order.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Object
   * @param {Object} object The object to inspect.
   * @param {Function} [predicate=_.identity] The function invoked per iteration.
   * @returns {string|undefined} Returns the key of the matched element,
   *  else `undefined`.
   * @example
   *
   * var users = {
   *   'barney':  { 'age': 36, 'active': true },
   *   'fred':    { 'age': 40, 'active': false },
   *   'pebbles': { 'age': 1,  'active': true }
   * };
   *
   * _.findLastKey(users, function(o) { return o.age < 40; });
   * // => returns 'pebbles' assuming `_.findKey` returns 'barney'
   *
   * // The `_.matches` iteratee shorthand.
   * _.findLastKey(users, { 'age': 36, 'active': true });
   * // => 'barney'
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.findLastKey(users, ['active', false]);
   * // => 'fred'
   *
   * // The `_.property` iteratee shorthand.
   * _.findLastKey(users, 'active');
   * // => 'pebbles'
   */
  function findLastKey(object, predicate) {
    return baseFindKey(object, getIteratee(predicate, 3), baseForOwnRight);
  }

  /**
   * Iterates over own and inherited enumerable string keyed properties of an
   * object and invokes `iteratee` for each property. The iteratee is invoked
   * with three arguments: (value, key, object). Iteratee functions may exit
   * iteration early by explicitly returning `false`.
   *
   * @static
   * @memberOf _
   * @since 0.3.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns `object`.
   * @see _.forInRight
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.forIn(new Foo, function(value, key) {
   *   console.log(key);
   * });
   * // => Logs 'a', 'b', then 'c' (iteration order is not guaranteed).
   */
  function forIn(object, iteratee) {
    return object == null
      ? object
      : baseFor(object, getIteratee(iteratee, 3), keysIn);
  }

  /**
   * This method is like `_.forIn` except that it iterates over properties of
   * `object` in the opposite order.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns `object`.
   * @see _.forIn
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.forInRight(new Foo, function(value, key) {
   *   console.log(key);
   * });
   * // => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'.
   */
  function forInRight(object, iteratee) {
    return object == null
      ? object
      : baseForRight(object, getIteratee(iteratee, 3), keysIn);
  }

  /**
   * Iterates over own enumerable string keyed properties of an object and
   * invokes `iteratee` for each property. The iteratee is invoked with three
   * arguments: (value, key, object). Iteratee functions may exit iteration
   * early by explicitly returning `false`.
   *
   * @static
   * @memberOf _
   * @since 0.3.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns `object`.
   * @see _.forOwnRight
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.forOwn(new Foo, function(value, key) {
   *   console.log(key);
   * });
   * // => Logs 'a' then 'b' (iteration order is not guaranteed).
   */
  function forOwn(object, iteratee) {
    return object && baseForOwn(object, getIteratee(iteratee, 3));
  }

  /**
   * This method is like `_.forOwn` except that it iterates over properties of
   * `object` in the opposite order.
   *
   * @static
   * @memberOf _
   * @since 2.0.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns `object`.
   * @see _.forOwn
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.forOwnRight(new Foo, function(value, key) {
   *   console.log(key);
   * });
   * // => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'.
   */
  function forOwnRight(object, iteratee) {
    return object && baseForOwnRight(object, getIteratee(iteratee, 3));
  }

  /**
   * Creates an array of function property names from own enumerable properties
   * of `object`.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The object to inspect.
   * @returns {Array} Returns the function names.
   * @see _.functionsIn
   * @example
   *
   * function Foo() {
   *   this.a = _.constant('a');
   *   this.b = _.constant('b');
   * }
   *
   * Foo.prototype.c = _.constant('c');
   *
   * _.functions(new Foo);
   * // => ['a', 'b']
   */
  function functions(object) {
    return object == null ? [] : baseFunctions(object, keys(object));
  }

  /**
   * Creates an array of function property names from own and inherited
   * enumerable properties of `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The object to inspect.
   * @returns {Array} Returns the function names.
   * @see _.functions
   * @example
   *
   * function Foo() {
   *   this.a = _.constant('a');
   *   this.b = _.constant('b');
   * }
   *
   * Foo.prototype.c = _.constant('c');
   *
   * _.functionsIn(new Foo);
   * // => ['a', 'b', 'c']
   */
  function functionsIn(object) {
    return object == null ? [] : baseFunctions(object, keysIn(object));
  }

  /**
   * Gets the value at `path` of `object`. If the resolved value is
   * `undefined`, the `defaultValue` is returned in its place.
   *
   * @static
   * @memberOf _
   * @since 3.7.0
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the property to get.
   * @param {*} [defaultValue] The value returned for `undefined` resolved values.
   * @returns {*} Returns the resolved value.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }] };
   *
   * _.get(object, 'a[0].b.c');
   * // => 3
   *
   * _.get(object, ['a', '0', 'b', 'c']);
   * // => 3
   *
   * _.get(object, 'a.b.c', 'default');
   * // => 'default'
   */
  function get(object, path, defaultValue) {
    var result = object == null ? undefined : baseGet(object, path);
    return result === undefined ? defaultValue : result;
  }

  /**
   * Checks if `path` is a direct property of `object`.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path to check.
   * @returns {boolean} Returns `true` if `path` exists, else `false`.
   * @example
   *
   * var object = { 'a': { 'b': 2 } };
   * var other = _.create({ 'a': _.create({ 'b': 2 }) });
   *
   * _.has(object, 'a');
   * // => true
   *
   * _.has(object, 'a.b');
   * // => true
   *
   * _.has(object, ['a', 'b']);
   * // => true
   *
   * _.has(other, 'a');
   * // => false
   */
  function has(object, path) {
    return object != null && hasPath(object, path, baseHas);
  }

  /**
   * Checks if `path` is a direct or inherited property of `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path to check.
   * @returns {boolean} Returns `true` if `path` exists, else `false`.
   * @example
   *
   * var object = _.create({ 'a': _.create({ 'b': 2 }) });
   *
   * _.hasIn(object, 'a');
   * // => true
   *
   * _.hasIn(object, 'a.b');
   * // => true
   *
   * _.hasIn(object, ['a', 'b']);
   * // => true
   *
   * _.hasIn(object, 'b');
   * // => false
   */
  function hasIn(object, path) {
    return object != null && hasPath(object, path, baseHasIn);
  }

  /**
   * Creates an object composed of the inverted keys and values of `object`.
   * If `object` contains duplicate values, subsequent values overwrite
   * property assignments of previous values.
   *
   * @static
   * @memberOf _
   * @since 0.7.0
   * @category Object
   * @param {Object} object The object to invert.
   * @returns {Object} Returns the new inverted object.
   * @example
   *
   * var object = { 'a': 1, 'b': 2, 'c': 1 };
   *
   * _.invert(object);
   * // => { '1': 'c', '2': 'b' }
   */
  var invert = createInverter(function(result, value, key) {
    if (value != null &&
        typeof value.toString != 'function') {
      value = nativeObjectToString.call(value);
    }

    result[value] = key;
  }, constant(identity));

  /**
   * This method is like `_.invert` except that the inverted object is generated
   * from the results of running each element of `object` thru `iteratee`. The
   * corresponding inverted value of each inverted key is an array of keys
   * responsible for generating the inverted value. The iteratee is invoked
   * with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.1.0
   * @category Object
   * @param {Object} object The object to invert.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {Object} Returns the new inverted object.
   * @example
   *
   * var object = { 'a': 1, 'b': 2, 'c': 1 };
   *
   * _.invertBy(object);
   * // => { '1': ['a', 'c'], '2': ['b'] }
   *
   * _.invertBy(object, function(value) {
   *   return 'group' + value;
   * });
   * // => { 'group1': ['a', 'c'], 'group2': ['b'] }
   */
  var invertBy = createInverter(function(result, value, key) {
    if (value != null &&
        typeof value.toString != 'function') {
      value = nativeObjectToString.call(value);
    }

    if (hasOwnProperty.call(result, value)) {
      result[value].push(key);
    } else {
      result[value] = [key];
    }
  }, getIteratee);

  /**
   * Invokes the method at `path` of `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the method to invoke.
   * @param {...*} [args] The arguments to invoke the method with.
   * @returns {*} Returns the result of the invoked method.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] };
   *
   * _.invoke(object, 'a[0].b.c.slice', 1, 3);
   * // => [2, 3]
   */
  var invoke = baseRest(baseInvoke);

  /**
   * Creates an array of the own enumerable property names of `object`.
   *
   * **Note:** Non-object values are coerced to objects. See the
   * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
   * for more details.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.keys(new Foo);
   * // => ['a', 'b'] (iteration order is not guaranteed)
   *
   * _.keys('hi');
   * // => ['0', '1']
   */
  function keys(object) {
    return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object);
  }

  /**
   * Creates an array of the own and inherited enumerable property names of `object`.
   *
   * **Note:** Non-object values are coerced to objects.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.keysIn(new Foo);
   * // => ['a', 'b', 'c'] (iteration order is not guaranteed)
   */
  function keysIn(object) {
    return isArrayLike(object) ? arrayLikeKeys(object, true) : baseKeysIn(object);
  }

  /**
   * The opposite of `_.mapValues`; this method creates an object with the
   * same values as `object` and keys generated by running each own enumerable
   * string keyed property of `object` thru `iteratee`. The iteratee is invoked
   * with three arguments: (value, key, object).
   *
   * @static
   * @memberOf _
   * @since 3.8.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns the new mapped object.
   * @see _.mapValues
   * @example
   *
   * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {
   *   return key + value;
   * });
   * // => { 'a1': 1, 'b2': 2 }
   */
  function mapKeys(object, iteratee) {
    var result = {};
    iteratee = getIteratee(iteratee, 3);

    baseForOwn(object, function(value, key, object) {
      baseAssignValue(result, iteratee(value, key, object), value);
    });
    return result;
  }

  /**
   * Creates an object with the same keys as `object` and values generated
   * by running each own enumerable string keyed property of `object` thru
   * `iteratee`. The iteratee is invoked with three arguments:
   * (value, key, object).
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Object} Returns the new mapped object.
   * @see _.mapKeys
   * @example
   *
   * var users = {
   *   'fred':    { 'user': 'fred',    'age': 40 },
   *   'pebbles': { 'user': 'pebbles', 'age': 1 }
   * };
   *
   * _.mapValues(users, function(o) { return o.age; });
   * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
   *
   * // The `_.property` iteratee shorthand.
   * _.mapValues(users, 'age');
   * // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
   */
  function mapValues(object, iteratee) {
    var result = {};
    iteratee = getIteratee(iteratee, 3);

    baseForOwn(object, function(value, key, object) {
      baseAssignValue(result, key, iteratee(value, key, object));
    });
    return result;
  }

  /**
   * This method is like `_.assign` except that it recursively merges own and
   * inherited enumerable string keyed properties of source objects into the
   * destination object. Source properties that resolve to `undefined` are
   * skipped if a destination value exists. Array and plain object properties
   * are merged recursively. Other objects and value types are overridden by
   * assignment. Source objects are applied from left to right. Subsequent
   * sources overwrite property assignments of previous sources.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 0.5.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = {
   *   'a': [{ 'b': 2 }, { 'd': 4 }]
   * };
   *
   * var other = {
   *   'a': [{ 'c': 3 }, { 'e': 5 }]
   * };
   *
   * _.merge(object, other);
   * // => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }
   */
  var merge = createAssigner(function(object, source, srcIndex) {
    baseMerge(object, source, srcIndex);
  });

  /**
   * This method is like `_.merge` except that it accepts `customizer` which
   * is invoked to produce the merged values of the destination and source
   * properties. If `customizer` returns `undefined`, merging is handled by the
   * method instead. The `customizer` is invoked with six arguments:
   * (objValue, srcValue, key, object, source, stack).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} sources The source objects.
   * @param {Function} customizer The function to customize assigned values.
   * @returns {Object} Returns `object`.
   * @example
   *
   * function customizer(objValue, srcValue) {
   *   if (_.isArray(objValue)) {
   *     return objValue.concat(srcValue);
   *   }
   * }
   *
   * var object = { 'a': [1], 'b': [2] };
   * var other = { 'a': [3], 'b': [4] };
   *
   * _.mergeWith(object, other, customizer);
   * // => { 'a': [1, 3], 'b': [2, 4] }
   */
  var mergeWith = createAssigner(function(object, source, srcIndex, customizer) {
    baseMerge(object, source, srcIndex, customizer);
  });

  /**
   * The opposite of `_.pick`; this method creates an object composed of the
   * own and inherited enumerable property paths of `object` that are not omitted.
   *
   * **Note:** This method is considerably slower than `_.pick`.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The source object.
   * @param {...(string|string[])} [paths] The property paths to omit.
   * @returns {Object} Returns the new object.
   * @example
   *
   * var object = { 'a': 1, 'b': '2', 'c': 3 };
   *
   * _.omit(object, ['a', 'c']);
   * // => { 'b': '2' }
   */
  var omit = flatRest(function(object, paths) {
    var result = {};
    if (object == null) {
      return result;
    }
    var isDeep = false;
    paths = arrayMap(paths, function(path) {
      path = castPath(path, object);
      isDeep || (isDeep = path.length > 1);
      return path;
    });
    copyObject(object, getAllKeysIn(object), result);
    if (isDeep) {
      result = baseClone(result, CLONE_DEEP_FLAG | CLONE_FLAT_FLAG | CLONE_SYMBOLS_FLAG, customOmitClone);
    }
    var length = paths.length;
    while (length--) {
      baseUnset(result, paths[length]);
    }
    return result;
  });

  /**
   * The opposite of `_.pickBy`; this method creates an object composed of
   * the own and inherited enumerable string keyed properties of `object` that
   * `predicate` doesn't return truthy for. The predicate is invoked with two
   * arguments: (value, key).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The source object.
   * @param {Function} [predicate=_.identity] The function invoked per property.
   * @returns {Object} Returns the new object.
   * @example
   *
   * var object = { 'a': 1, 'b': '2', 'c': 3 };
   *
   * _.omitBy(object, _.isNumber);
   * // => { 'b': '2' }
   */
  function omitBy(object, predicate) {
    return pickBy(object, negate(getIteratee(predicate)));
  }

  /**
   * Creates an object composed of the picked `object` properties.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The source object.
   * @param {...(string|string[])} [paths] The property paths to pick.
   * @returns {Object} Returns the new object.
   * @example
   *
   * var object = { 'a': 1, 'b': '2', 'c': 3 };
   *
   * _.pick(object, ['a', 'c']);
   * // => { 'a': 1, 'c': 3 }
   */
  var pick = flatRest(function(object, paths) {
    return object == null ? {} : basePick(object, paths);
  });

  /**
   * Creates an object composed of the `object` properties `predicate` returns
   * truthy for. The predicate is invoked with two arguments: (value, key).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The source object.
   * @param {Function} [predicate=_.identity] The function invoked per property.
   * @returns {Object} Returns the new object.
   * @example
   *
   * var object = { 'a': 1, 'b': '2', 'c': 3 };
   *
   * _.pickBy(object, _.isNumber);
   * // => { 'a': 1, 'c': 3 }
   */
  function pickBy(object, predicate) {
    if (object == null) {
      return {};
    }
    var props = arrayMap(getAllKeysIn(object), function(prop) {
      return [prop];
    });
    predicate = getIteratee(predicate);
    return basePickBy(object, props, function(value, path) {
      return predicate(value, path[0]);
    });
  }

  /**
   * This method is like `_.get` except that if the resolved value is a
   * function it's invoked with the `this` binding of its parent object and
   * its result is returned.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the property to resolve.
   * @param {*} [defaultValue] The value returned for `undefined` resolved values.
   * @returns {*} Returns the resolved value.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };
   *
   * _.result(object, 'a[0].b.c1');
   * // => 3
   *
   * _.result(object, 'a[0].b.c2');
   * // => 4
   *
   * _.result(object, 'a[0].b.c3', 'default');
   * // => 'default'
   *
   * _.result(object, 'a[0].b.c3', _.constant('default'));
   * // => 'default'
   */
  function result(object, path, defaultValue) {
    path = castPath(path, object);

    var index = -1,
        length = path.length;

    // Ensure the loop is entered when path is empty.
    if (!length) {
      length = 1;
      object = undefined;
    }
    while (++index < length) {
      var value = object == null ? undefined : object[toKey(path[index])];
      if (value === undefined) {
        index = length;
        value = defaultValue;
      }
      object = isFunction(value) ? value.call(object) : value;
    }
    return object;
  }

  /**
   * Sets the value at `path` of `object`. If a portion of `path` doesn't exist,
   * it's created. Arrays are created for missing index properties while objects
   * are created for all other missing properties. Use `_.setWith` to customize
   * `path` creation.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 3.7.0
   * @category Object
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }] };
   *
   * _.set(object, 'a[0].b.c', 4);
   * console.log(object.a[0].b.c);
   * // => 4
   *
   * _.set(object, ['x', '0', 'y', 'z'], 5);
   * console.log(object.x[0].y.z);
   * // => 5
   */
  function set(object, path, value) {
    return object == null ? object : baseSet(object, path, value);
  }

  /**
   * This method is like `_.set` except that it accepts `customizer` which is
   * invoked to produce the objects of `path`.  If `customizer` returns `undefined`
   * path creation is handled by the method instead. The `customizer` is invoked
   * with three arguments: (nsValue, key, nsObject).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to set.
   * @param {*} value The value to set.
   * @param {Function} [customizer] The function to customize assigned values.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = {};
   *
   * _.setWith(object, '[0][1]', 'a', Object);
   * // => { '0': { '1': 'a' } }
   */
  function setWith(object, path, value, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    return object == null ? object : baseSet(object, path, value, customizer);
  }

  /**
   * Creates an array of own enumerable string keyed-value pairs for `object`
   * which can be consumed by `_.fromPairs`. If `object` is a map or set, its
   * entries are returned.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @alias entries
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the key-value pairs.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.toPairs(new Foo);
   * // => [['a', 1], ['b', 2]] (iteration order is not guaranteed)
   */
  var toPairs = createToPairs(keys);

  /**
   * Creates an array of own and inherited enumerable string keyed-value pairs
   * for `object` which can be consumed by `_.fromPairs`. If `object` is a map
   * or set, its entries are returned.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @alias entriesIn
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the key-value pairs.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.toPairsIn(new Foo);
   * // => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed)
   */
  var toPairsIn = createToPairs(keysIn);

  /**
   * An alternative to `_.reduce`; this method transforms `object` to a new
   * `accumulator` object which is the result of running each of its own
   * enumerable string keyed properties thru `iteratee`, with each invocation
   * potentially mutating the `accumulator` object. If `accumulator` is not
   * provided, a new object with the same `[[Prototype]]` will be used. The
   * iteratee is invoked with four arguments: (accumulator, value, key, object).
   * Iteratee functions may exit iteration early by explicitly returning `false`.
   *
   * @static
   * @memberOf _
   * @since 1.3.0
   * @category Object
   * @param {Object} object The object to iterate over.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @param {*} [accumulator] The custom accumulator value.
   * @returns {*} Returns the accumulated value.
   * @example
   *
   * _.transform([2, 3, 4], function(result, n) {
   *   result.push(n *= n);
   *   return n % 2 == 0;
   * }, []);
   * // => [4, 9]
   *
   * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
   *   (result[value] || (result[value] = [])).push(key);
   * }, {});
   * // => { '1': ['a', 'c'], '2': ['b'] }
   */
  function transform(object, iteratee, accumulator) {
    var isArr = isArray(object),
        isArrLike = isArr || isBuffer(object) || isTypedArray(object);

    iteratee = getIteratee(iteratee, 4);
    if (accumulator == null) {
      var Ctor = object && object.constructor;
      if (isArrLike) {
        accumulator = isArr ? new Ctor : [];
      }
      else if (isObject(object)) {
        accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {};
      }
      else {
        accumulator = {};
      }
    }
    (isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) {
      return iteratee(accumulator, value, index, object);
    });
    return accumulator;
  }

  /**
   * Removes the property at `path` of `object`.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Object
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to unset.
   * @returns {boolean} Returns `true` if the property is deleted, else `false`.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 7 } }] };
   * _.unset(object, 'a[0].b.c');
   * // => true
   *
   * console.log(object);
   * // => { 'a': [{ 'b': {} }] };
   *
   * _.unset(object, ['a', '0', 'b', 'c']);
   * // => true
   *
   * console.log(object);
   * // => { 'a': [{ 'b': {} }] };
   */
  function unset(object, path) {
    return object == null ? true : baseUnset(object, path);
  }

  /**
   * This method is like `_.set` except that accepts `updater` to produce the
   * value to set. Use `_.updateWith` to customize `path` creation. The `updater`
   * is invoked with one argument: (value).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.6.0
   * @category Object
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to set.
   * @param {Function} updater The function to produce the updated value.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }] };
   *
   * _.update(object, 'a[0].b.c', function(n) { return n * n; });
   * console.log(object.a[0].b.c);
   * // => 9
   *
   * _.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; });
   * console.log(object.x[0].y.z);
   * // => 0
   */
  function update(object, path, updater) {
    return object == null ? object : baseUpdate(object, path, castFunction(updater));
  }

  /**
   * This method is like `_.update` except that it accepts `customizer` which is
   * invoked to produce the objects of `path`.  If `customizer` returns `undefined`
   * path creation is handled by the method instead. The `customizer` is invoked
   * with three arguments: (nsValue, key, nsObject).
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 4.6.0
   * @category Object
   * @param {Object} object The object to modify.
   * @param {Array|string} path The path of the property to set.
   * @param {Function} updater The function to produce the updated value.
   * @param {Function} [customizer] The function to customize assigned values.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = {};
   *
   * _.updateWith(object, '[0][1]', _.constant('a'), Object);
   * // => { '0': { '1': 'a' } }
   */
  function updateWith(object, path, updater, customizer) {
    customizer = typeof customizer == 'function' ? customizer : undefined;
    return object == null ? object : baseUpdate(object, path, castFunction(updater), customizer);
  }

  /**
   * Creates an array of the own enumerable string keyed property values of `object`.
   *
   * **Note:** Non-object values are coerced to objects.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property values.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.values(new Foo);
   * // => [1, 2] (iteration order is not guaranteed)
   *
   * _.values('hi');
   * // => ['h', 'i']
   */
  function values(object) {
    return object == null ? [] : baseValues(object, keys(object));
  }

  /**
   * Creates an array of the own and inherited enumerable string keyed property
   * values of `object`.
   *
   * **Note:** Non-object values are coerced to objects.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Object
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property values.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.valuesIn(new Foo);
   * // => [1, 2, 3] (iteration order is not guaranteed)
   */
  function valuesIn(object) {
    return object == null ? [] : baseValues(object, keysIn(object));
  }

  /*------------------------------------------------------------------------*/

  /**
   * Clamps `number` within the inclusive `lower` and `upper` bounds.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Number
   * @param {number} number The number to clamp.
   * @param {number} [lower] The lower bound.
   * @param {number} upper The upper bound.
   * @returns {number} Returns the clamped number.
   * @example
   *
   * _.clamp(-10, -5, 5);
   * // => -5
   *
   * _.clamp(10, -5, 5);
   * // => 5
   */
  function clamp(number, lower, upper) {
    if (upper === undefined) {
      upper = lower;
      lower = undefined;
    }
    if (upper !== undefined) {
      upper = toNumber(upper);
      upper = upper === upper ? upper : 0;
    }
    if (lower !== undefined) {
      lower = toNumber(lower);
      lower = lower === lower ? lower : 0;
    }
    return baseClamp(toNumber(number), lower, upper);
  }

  /**
   * Checks if `n` is between `start` and up to, but not including, `end`. If
   * `end` is not specified, it's set to `start` with `start` then set to `0`.
   * If `start` is greater than `end` the params are swapped to support
   * negative ranges.
   *
   * @static
   * @memberOf _
   * @since 3.3.0
   * @category Number
   * @param {number} number The number to check.
   * @param {number} [start=0] The start of the range.
   * @param {number} end The end of the range.
   * @returns {boolean} Returns `true` if `number` is in the range, else `false`.
   * @see _.range, _.rangeRight
   * @example
   *
   * _.inRange(3, 2, 4);
   * // => true
   *
   * _.inRange(4, 8);
   * // => true
   *
   * _.inRange(4, 2);
   * // => false
   *
   * _.inRange(2, 2);
   * // => false
   *
   * _.inRange(1.2, 2);
   * // => true
   *
   * _.inRange(5.2, 4);
   * // => false
   *
   * _.inRange(-3, -2, -6);
   * // => true
   */
  function inRange(number, start, end) {
    start = toFinite(start);
    if (end === undefined) {
      end = start;
      start = 0;
    } else {
      end = toFinite(end);
    }
    number = toNumber(number);
    return baseInRange(number, start, end);
  }

  /**
   * Produces a random number between the inclusive `lower` and `upper` bounds.
   * If only one argument is provided a number between `0` and the given number
   * is returned. If `floating` is `true`, or either `lower` or `upper` are
   * floats, a floating-point number is returned instead of an integer.
   *
   * **Note:** JavaScript follows the IEEE-754 standard for resolving
   * floating-point values which can produce unexpected results.
   *
   * @static
   * @memberOf _
   * @since 0.7.0
   * @category Number
   * @param {number} [lower=0] The lower bound.
   * @param {number} [upper=1] The upper bound.
   * @param {boolean} [floating] Specify returning a floating-point number.
   * @returns {number} Returns the random number.
   * @example
   *
   * _.random(0, 5);
   * // => an integer between 0 and 5
   *
   * _.random(5);
   * // => also an integer between 0 and 5
   *
   * _.random(5, true);
   * // => a floating-point number between 0 and 5
   *
   * _.random(1.2, 5.2);
   * // => a floating-point number between 1.2 and 5.2
   */
  function random(lower, upper, floating) {
    if (floating && typeof floating != 'boolean' && isIterateeCall(lower, upper, floating)) {
      upper = floating = undefined;
    }
    if (floating === undefined) {
      if (typeof upper == 'boolean') {
        floating = upper;
        upper = undefined;
      }
      else if (typeof lower == 'boolean') {
        floating = lower;
        lower = undefined;
      }
    }
    if (lower === undefined && upper === undefined) {
      lower = 0;
      upper = 1;
    }
    else {
      lower = toFinite(lower);
      if (upper === undefined) {
        upper = lower;
        lower = 0;
      } else {
        upper = toFinite(upper);
      }
    }
    if (lower > upper) {
      var temp = lower;
      lower = upper;
      upper = temp;
    }
    if (floating || lower % 1 || upper % 1) {
      var rand = nativeRandom();
      return nativeMin(lower + (rand * (upper - lower + freeParseFloat('1e-' + ((rand + '').length - 1)))), upper);
    }
    return baseRandom(lower, upper);
  }

  /*------------------------------------------------------------------------*/

  /**
   * Converts `string` to [camel case](https://en.wikipedia.org/wiki/CamelCase).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the camel cased string.
   * @example
   *
   * _.camelCase('Foo Bar');
   * // => 'fooBar'
   *
   * _.camelCase('--foo-bar--');
   * // => 'fooBar'
   *
   * _.camelCase('__FOO_BAR__');
   * // => 'fooBar'
   */
  var camelCase = createCompounder(function(result, word, index) {
    word = word.toLowerCase();
    return result + (index ? capitalize(word) : word);
  });

  /**
   * Converts the first character of `string` to upper case and the remaining
   * to lower case.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to capitalize.
   * @returns {string} Returns the capitalized string.
   * @example
   *
   * _.capitalize('FRED');
   * // => 'Fred'
   */
  function capitalize(string) {
    return upperFirst(toString(string).toLowerCase());
  }

  /**
   * Deburrs `string` by converting
   * [Latin-1 Supplement](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table)
   * and [Latin Extended-A](https://en.wikipedia.org/wiki/Latin_Extended-A)
   * letters to basic Latin letters and removing
   * [combining diacritical marks](https://en.wikipedia.org/wiki/Combining_Diacritical_Marks).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to deburr.
   * @returns {string} Returns the deburred string.
   * @example
   *
   * _.deburr('déjà vu');
   * // => 'deja vu'
   */
  function deburr(string) {
    string = toString(string);
    return string && string.replace(reLatin, deburrLetter).replace(reComboMark, '');
  }

  /**
   * Checks if `string` ends with the given target string.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to inspect.
   * @param {string} [target] The string to search for.
   * @param {number} [position=string.length] The position to search up to.
   * @returns {boolean} Returns `true` if `string` ends with `target`,
   *  else `false`.
   * @example
   *
   * _.endsWith('abc', 'c');
   * // => true
   *
   * _.endsWith('abc', 'b');
   * // => false
   *
   * _.endsWith('abc', 'b', 2);
   * // => true
   */
  function endsWith(string, target, position) {
    string = toString(string);
    target = baseToString(target);

    var length = string.length;
    position = position === undefined
      ? length
      : baseClamp(toInteger(position), 0, length);

    var end = position;
    position -= target.length;
    return position >= 0 && string.slice(position, end) == target;
  }

  /**
   * Converts the characters "&", "<", ">", '"', and "'" in `string` to their
   * corresponding HTML entities.
   *
   * **Note:** No other characters are escaped. To escape additional
   * characters use a third-party library like [_he_](https://mths.be/he).
   *
   * Though the ">" character is escaped for symmetry, characters like
   * ">" and "/" don't need escaping in HTML and have no special meaning
   * unless they're part of a tag or unquoted attribute value. See
   * [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands)
   * (under "semi-related fun fact") for more details.
   *
   * When working with HTML you should always
   * [quote attribute values](http://wonko.com/post/html-escaping) to reduce
   * XSS vectors.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category String
   * @param {string} [string=''] The string to escape.
   * @returns {string} Returns the escaped string.
   * @example
   *
   * _.escape('fred, barney, & pebbles');
   * // => 'fred, barney, &amp; pebbles'
   */
  function escape(string) {
    string = toString(string);
    return (string && reHasUnescapedHtml.test(string))
      ? string.replace(reUnescapedHtml, escapeHtmlChar)
      : string;
  }

  /**
   * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+",
   * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to escape.
   * @returns {string} Returns the escaped string.
   * @example
   *
   * _.escapeRegExp('[lodash](https://lodash.com/)');
   * // => '\[lodash\]\(https://lodash\.com/\)'
   */
  function escapeRegExp(string) {
    string = toString(string);
    return (string && reHasRegExpChar.test(string))
      ? string.replace(reRegExpChar, '\\$&')
      : string;
  }

  /**
   * Converts `string` to
   * [kebab case](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the kebab cased string.
   * @example
   *
   * _.kebabCase('Foo Bar');
   * // => 'foo-bar'
   *
   * _.kebabCase('fooBar');
   * // => 'foo-bar'
   *
   * _.kebabCase('__FOO_BAR__');
   * // => 'foo-bar'
   */
  var kebabCase = createCompounder(function(result, word, index) {
    return result + (index ? '-' : '') + word.toLowerCase();
  });

  /**
   * Converts `string`, as space separated words, to lower case.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the lower cased string.
   * @example
   *
   * _.lowerCase('--Foo-Bar--');
   * // => 'foo bar'
   *
   * _.lowerCase('fooBar');
   * // => 'foo bar'
   *
   * _.lowerCase('__FOO_BAR__');
   * // => 'foo bar'
   */
  var lowerCase = createCompounder(function(result, word, index) {
    return result + (index ? ' ' : '') + word.toLowerCase();
  });

  /**
   * Converts the first character of `string` to lower case.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the converted string.
   * @example
   *
   * _.lowerFirst('Fred');
   * // => 'fred'
   *
   * _.lowerFirst('FRED');
   * // => 'fRED'
   */
  var lowerFirst = createCaseFirst('toLowerCase');

  /**
   * Pads `string` on the left and right sides if it's shorter than `length`.
   * Padding characters are truncated if they can't be evenly divided by `length`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to pad.
   * @param {number} [length=0] The padding length.
   * @param {string} [chars=' '] The string used as padding.
   * @returns {string} Returns the padded string.
   * @example
   *
   * _.pad('abc', 8);
   * // => '  abc   '
   *
   * _.pad('abc', 8, '_-');
   * // => '_-abc_-_'
   *
   * _.pad('abc', 3);
   * // => 'abc'
   */
  function pad(string, length, chars) {
    string = toString(string);
    length = toInteger(length);

    var strLength = length ? stringSize(string) : 0;
    if (!length || strLength >= length) {
      return string;
    }
    var mid = (length - strLength) / 2;
    return (
      createPadding(nativeFloor(mid), chars) +
      string +
      createPadding(nativeCeil(mid), chars)
    );
  }

  /**
   * Pads `string` on the right side if it's shorter than `length`. Padding
   * characters are truncated if they exceed `length`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to pad.
   * @param {number} [length=0] The padding length.
   * @param {string} [chars=' '] The string used as padding.
   * @returns {string} Returns the padded string.
   * @example
   *
   * _.padEnd('abc', 6);
   * // => 'abc   '
   *
   * _.padEnd('abc', 6, '_-');
   * // => 'abc_-_'
   *
   * _.padEnd('abc', 3);
   * // => 'abc'
   */
  function padEnd(string, length, chars) {
    string = toString(string);
    length = toInteger(length);

    var strLength = length ? stringSize(string) : 0;
    return (length && strLength < length)
      ? (string + createPadding(length - strLength, chars))
      : string;
  }

  /**
   * Pads `string` on the left side if it's shorter than `length`. Padding
   * characters are truncated if they exceed `length`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to pad.
   * @param {number} [length=0] The padding length.
   * @param {string} [chars=' '] The string used as padding.
   * @returns {string} Returns the padded string.
   * @example
   *
   * _.padStart('abc', 6);
   * // => '   abc'
   *
   * _.padStart('abc', 6, '_-');
   * // => '_-_abc'
   *
   * _.padStart('abc', 3);
   * // => 'abc'
   */
  function padStart(string, length, chars) {
    string = toString(string);
    length = toInteger(length);

    var strLength = length ? stringSize(string) : 0;
    return (length && strLength < length)
      ? (createPadding(length - strLength, chars) + string)
      : string;
  }

  /**
   * Converts `string` to an integer of the specified radix. If `radix` is
   * `undefined` or `0`, a `radix` of `10` is used unless `value` is a
   * hexadecimal, in which case a `radix` of `16` is used.
   *
   * **Note:** This method aligns with the
   * [ES5 implementation](https://es5.github.io/#x15.1.2.2) of `parseInt`.
   *
   * @static
   * @memberOf _
   * @since 1.1.0
   * @category String
   * @param {string} string The string to convert.
   * @param {number} [radix=10] The radix to interpret `value` by.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {number} Returns the converted integer.
   * @example
   *
   * _.parseInt('08');
   * // => 8
   *
   * _.map(['6', '08', '10'], _.parseInt);
   * // => [6, 8, 10]
   */
  function parseInt(string, radix, guard) {
    if (guard || radix == null) {
      radix = 0;
    } else if (radix) {
      radix = +radix;
    }
    return nativeParseInt(toString(string).replace(reTrimStart, ''), radix || 0);
  }

  /**
   * Repeats the given string `n` times.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to repeat.
   * @param {number} [n=1] The number of times to repeat the string.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {string} Returns the repeated string.
   * @example
   *
   * _.repeat('*', 3);
   * // => '***'
   *
   * _.repeat('abc', 2);
   * // => 'abcabc'
   *
   * _.repeat('abc', 0);
   * // => ''
   */
  function repeat(string, n, guard) {
    if ((guard ? isIterateeCall(string, n, guard) : n === undefined)) {
      n = 1;
    } else {
      n = toInteger(n);
    }
    return baseRepeat(toString(string), n);
  }

  /**
   * Replaces matches for `pattern` in `string` with `replacement`.
   *
   * **Note:** This method is based on
   * [`String#replace`](https://mdn.io/String/replace).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to modify.
   * @param {RegExp|string} pattern The pattern to replace.
   * @param {Function|string} replacement The match replacement.
   * @returns {string} Returns the modified string.
   * @example
   *
   * _.replace('Hi Fred', 'Fred', 'Barney');
   * // => 'Hi Barney'
   */
  function replace() {
    var args = arguments,
        string = toString(args[0]);

    return args.length < 3 ? string : string.replace(args[1], args[2]);
  }

  /**
   * Converts `string` to
   * [snake case](https://en.wikipedia.org/wiki/Snake_case).
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the snake cased string.
   * @example
   *
   * _.snakeCase('Foo Bar');
   * // => 'foo_bar'
   *
   * _.snakeCase('fooBar');
   * // => 'foo_bar'
   *
   * _.snakeCase('--FOO-BAR--');
   * // => 'foo_bar'
   */
  var snakeCase = createCompounder(function(result, word, index) {
    return result + (index ? '_' : '') + word.toLowerCase();
  });

  /**
   * Splits `string` by `separator`.
   *
   * **Note:** This method is based on
   * [`String#split`](https://mdn.io/String/split).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to split.
   * @param {RegExp|string} separator The separator pattern to split by.
   * @param {number} [limit] The length to truncate results to.
   * @returns {Array} Returns the string segments.
   * @example
   *
   * _.split('a-b-c', '-', 2);
   * // => ['a', 'b']
   */
  function split(string, separator, limit) {
    if (limit && typeof limit != 'number' && isIterateeCall(string, separator, limit)) {
      separator = limit = undefined;
    }
    limit = limit === undefined ? MAX_ARRAY_LENGTH : limit >>> 0;
    if (!limit) {
      return [];
    }
    string = toString(string);
    if (string && (
          typeof separator == 'string' ||
          (separator != null && !isRegExp(separator))
        )) {
      separator = baseToString(separator);
      if (!separator && hasUnicode(string)) {
        return castSlice(stringToArray(string), 0, limit);
      }
    }
    return string.split(separator, limit);
  }

  /**
   * Converts `string` to
   * [start case](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage).
   *
   * @static
   * @memberOf _
   * @since 3.1.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the start cased string.
   * @example
   *
   * _.startCase('--foo-bar--');
   * // => 'Foo Bar'
   *
   * _.startCase('fooBar');
   * // => 'Foo Bar'
   *
   * _.startCase('__FOO_BAR__');
   * // => 'FOO BAR'
   */
  var startCase = createCompounder(function(result, word, index) {
    return result + (index ? ' ' : '') + upperFirst(word);
  });

  /**
   * Checks if `string` starts with the given target string.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to inspect.
   * @param {string} [target] The string to search for.
   * @param {number} [position=0] The position to search from.
   * @returns {boolean} Returns `true` if `string` starts with `target`,
   *  else `false`.
   * @example
   *
   * _.startsWith('abc', 'a');
   * // => true
   *
   * _.startsWith('abc', 'b');
   * // => false
   *
   * _.startsWith('abc', 'b', 1);
   * // => true
   */
  function startsWith(string, target, position) {
    string = toString(string);
    position = position == null
      ? 0
      : baseClamp(toInteger(position), 0, string.length);

    target = baseToString(target);
    return string.slice(position, position + target.length) == target;
  }

  /**
   * Creates a compiled template function that can interpolate data properties
   * in "interpolate" delimiters, HTML-escape interpolated data properties in
   * "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
   * properties may be accessed as free variables in the template. If a setting
   * object is given, it takes precedence over `_.templateSettings` values.
   *
   * **Note:** In the development build `_.template` utilizes
   * [sourceURLs](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)
   * for easier debugging.
   *
   * For more information on precompiling templates see
   * [lodash's custom builds documentation](https://lodash.com/custom-builds).
   *
   * For more information on Chrome extension sandboxes see
   * [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval).
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category String
   * @param {string} [string=''] The template string.
   * @param {Object} [options={}] The options object.
   * @param {RegExp} [options.escape=_.templateSettings.escape]
   *  The HTML "escape" delimiter.
   * @param {RegExp} [options.evaluate=_.templateSettings.evaluate]
   *  The "evaluate" delimiter.
   * @param {Object} [options.imports=_.templateSettings.imports]
   *  An object to import into the template as free variables.
   * @param {RegExp} [options.interpolate=_.templateSettings.interpolate]
   *  The "interpolate" delimiter.
   * @param {string} [options.sourceURL='lodash.templateSources[n]']
   *  The sourceURL of the compiled template.
   * @param {string} [options.variable='obj']
   *  The data object variable name.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Function} Returns the compiled template function.
   * @example
   *
   * // Use the "interpolate" delimiter to create a compiled template.
   * var compiled = _.template('hello <%= user %>!');
   * compiled({ 'user': 'fred' });
   * // => 'hello fred!'
   *
   * // Use the HTML "escape" delimiter to escape data property values.
   * var compiled = _.template('<b><%- value %></b>');
   * compiled({ 'value': '<script>' });
   * // => '<b>&lt;script&gt;</b>'
   *
   * // Use the "evaluate" delimiter to execute JavaScript and generate HTML.
   * var compiled = _.template('<% _.forEach(users, function(user) { %><li><%- user %></li><% }); %>');
   * compiled({ 'users': ['fred', 'barney'] });
   * // => '<li>fred</li><li>barney</li>'
   *
   * // Use the internal `print` function in "evaluate" delimiters.
   * var compiled = _.template('<% print("hello " + user); %>!');
   * compiled({ 'user': 'barney' });
   * // => 'hello barney!'
   *
   * // Use the ES template literal delimiter as an "interpolate" delimiter.
   * // Disable support by replacing the "interpolate" delimiter.
   * var compiled = _.template('hello ${ user }!');
   * compiled({ 'user': 'pebbles' });
   * // => 'hello pebbles!'
   *
   * // Use backslashes to treat delimiters as plain text.
   * var compiled = _.template('<%= "\\<%- value %\\>" %>');
   * compiled({ 'value': 'ignored' });
   * // => '<%- value %>'
   *
   * // Use the `imports` option to import `jQuery` as `jq`.
   * var text = '<% jq.each(users, function(user) { %><li><%- user %></li><% }); %>';
   * var compiled = _.template(text, { 'imports': { 'jq': jQuery } });
   * compiled({ 'users': ['fred', 'barney'] });
   * // => '<li>fred</li><li>barney</li>'
   *
   * // Use the `sourceURL` option to specify a custom sourceURL for the template.
   * var compiled = _.template('hello <%= user %>!', { 'sourceURL': '/basic/greeting.jst' });
   * compiled(data);
   * // => Find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector.
   *
   * // Use the `variable` option to ensure a with-statement isn't used in the compiled template.
   * var compiled = _.template('hi <%= data.user %>!', { 'variable': 'data' });
   * compiled.source;
   * // => function(data) {
   * //   var __t, __p = '';
   * //   __p += 'hi ' + ((__t = ( data.user )) == null ? '' : __t) + '!';
   * //   return __p;
   * // }
   *
   * // Use custom template delimiters.
   * _.templateSettings.interpolate = /{{([\s\S]+?)}}/g;
   * var compiled = _.template('hello {{ user }}!');
   * compiled({ 'user': 'mustache' });
   * // => 'hello mustache!'
   *
   * // Use the `source` property to inline compiled templates for meaningful
   * // line numbers in error messages and stack traces.
   * fs.writeFileSync(path.join(process.cwd(), 'jst.js'), '\
   *   var JST = {\
   *     "main": ' + _.template(mainText).source + '\
   *   };\
   * ');
   */
  function template(string, options, guard) {
    // Based on John Resig's `tmpl` implementation
    // (http://ejohn.org/blog/javascript-micro-templating/)
    // and Laura Doktorova's doT.js (https://github.com/olado/doT).
    var settings = lodash.templateSettings;

    if (guard && isIterateeCall(string, options, guard)) {
      options = undefined;
    }
    string = toString(string);
    options = assignInWith({}, options, settings, customDefaultsAssignIn);

    var imports = assignInWith({}, options.imports, settings.imports, customDefaultsAssignIn),
        importsKeys = keys(imports),
        importsValues = baseValues(imports, importsKeys);

    var isEscaping,
        isEvaluating,
        index = 0,
        interpolate = options.interpolate || reNoMatch,
        source = "__p += '";

    // Compile the regexp to match each delimiter.
    var reDelimiters = RegExp(
      (options.escape || reNoMatch).source + '|' +
      interpolate.source + '|' +
      (interpolate === reInterpolate ? reEsTemplate : reNoMatch).source + '|' +
      (options.evaluate || reNoMatch).source + '|$'
    , 'g');

    // Use a sourceURL for easier debugging.
    // The sourceURL gets injected into the source that's eval-ed, so be careful
    // with lookup (in case of e.g. prototype pollution), and strip newlines if any.
    // A newline wouldn't be a valid sourceURL anyway, and it'd enable code injection.
    var sourceURL = '//# sourceURL=' +
      (hasOwnProperty.call(options, 'sourceURL')
        ? (options.sourceURL + '').replace(/[\r\n]/g, ' ')
        : ('lodash.templateSources[' + (++templateCounter) + ']')
      ) + '\n';

    string.replace(reDelimiters, function(match, escapeValue, interpolateValue, esTemplateValue, evaluateValue, offset) {
      interpolateValue || (interpolateValue = esTemplateValue);

      // Escape characters that can't be included in string literals.
      source += string.slice(index, offset).replace(reUnescapedString, escapeStringChar);

      // Replace delimiters with snippets.
      if (escapeValue) {
        isEscaping = true;
        source += "' +\n__e(" + escapeValue + ") +\n'";
      }
      if (evaluateValue) {
        isEvaluating = true;
        source += "';\n" + evaluateValue + ";\n__p += '";
      }
      if (interpolateValue) {
        source += "' +\n((__t = (" + interpolateValue + ")) == null ? '' : __t) +\n'";
      }
      index = offset + match.length;

      // The JS engine embedded in Adobe products needs `match` returned in
      // order to produce the correct `offset` value.
      return match;
    });

    source += "';\n";

    // If `variable` is not specified wrap a with-statement around the generated
    // code to add the data object to the top of the scope chain.
    // Like with sourceURL, we take care to not check the option's prototype,
    // as this configuration is a code injection vector.
    var variable = hasOwnProperty.call(options, 'variable') && options.variable;
    if (!variable) {
      source = 'with (obj) {\n' + source + '\n}\n';
    }
    // Cleanup code by stripping empty strings.
    source = (isEvaluating ? source.replace(reEmptyStringLeading, '') : source)
      .replace(reEmptyStringMiddle, '$1')
      .replace(reEmptyStringTrailing, '$1;');

    // Frame code as the function body.
    source = 'function(' + (variable || 'obj') + ') {\n' +
      (variable
        ? ''
        : 'obj || (obj = {});\n'
      ) +
      "var __t, __p = ''" +
      (isEscaping
         ? ', __e = _.escape'
         : ''
      ) +
      (isEvaluating
        ? ', __j = Array.prototype.join;\n' +
          "function print() { __p += __j.call(arguments, '') }\n"
        : ';\n'
      ) +
      source +
      'return __p\n}';

    var result = attempt(function() {
      return Function(importsKeys, sourceURL + 'return ' + source)
        .apply(undefined, importsValues);
    });

    // Provide the compiled function's source by its `toString` method or
    // the `source` property as a convenience for inlining compiled templates.
    result.source = source;
    if (isError(result)) {
      throw result;
    }
    return result;
  }

  /**
   * Converts `string`, as a whole, to lower case just like
   * [String#toLowerCase](https://mdn.io/toLowerCase).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the lower cased string.
   * @example
   *
   * _.toLower('--Foo-Bar--');
   * // => '--foo-bar--'
   *
   * _.toLower('fooBar');
   * // => 'foobar'
   *
   * _.toLower('__FOO_BAR__');
   * // => '__foo_bar__'
   */
  function toLower(value) {
    return toString(value).toLowerCase();
  }

  /**
   * Converts `string`, as a whole, to upper case just like
   * [String#toUpperCase](https://mdn.io/toUpperCase).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the upper cased string.
   * @example
   *
   * _.toUpper('--foo-bar--');
   * // => '--FOO-BAR--'
   *
   * _.toUpper('fooBar');
   * // => 'FOOBAR'
   *
   * _.toUpper('__foo_bar__');
   * // => '__FOO_BAR__'
   */
  function toUpper(value) {
    return toString(value).toUpperCase();
  }

  /**
   * Removes leading and trailing whitespace or specified characters from `string`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to trim.
   * @param {string} [chars=whitespace] The characters to trim.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {string} Returns the trimmed string.
   * @example
   *
   * _.trim('  abc  ');
   * // => 'abc'
   *
   * _.trim('-_-abc-_-', '_-');
   * // => 'abc'
   *
   * _.map(['  foo  ', '  bar  '], _.trim);
   * // => ['foo', 'bar']
   */
  function trim(string, chars, guard) {
    string = toString(string);
    if (string && (guard || chars === undefined)) {
      return string.replace(reTrim, '');
    }
    if (!string || !(chars = baseToString(chars))) {
      return string;
    }
    var strSymbols = stringToArray(string),
        chrSymbols = stringToArray(chars),
        start = charsStartIndex(strSymbols, chrSymbols),
        end = charsEndIndex(strSymbols, chrSymbols) + 1;

    return castSlice(strSymbols, start, end).join('');
  }

  /**
   * Removes trailing whitespace or specified characters from `string`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to trim.
   * @param {string} [chars=whitespace] The characters to trim.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {string} Returns the trimmed string.
   * @example
   *
   * _.trimEnd('  abc  ');
   * // => '  abc'
   *
   * _.trimEnd('-_-abc-_-', '_-');
   * // => '-_-abc'
   */
  function trimEnd(string, chars, guard) {
    string = toString(string);
    if (string && (guard || chars === undefined)) {
      return string.replace(reTrimEnd, '');
    }
    if (!string || !(chars = baseToString(chars))) {
      return string;
    }
    var strSymbols = stringToArray(string),
        end = charsEndIndex(strSymbols, stringToArray(chars)) + 1;

    return castSlice(strSymbols, 0, end).join('');
  }

  /**
   * Removes leading whitespace or specified characters from `string`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to trim.
   * @param {string} [chars=whitespace] The characters to trim.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {string} Returns the trimmed string.
   * @example
   *
   * _.trimStart('  abc  ');
   * // => 'abc  '
   *
   * _.trimStart('-_-abc-_-', '_-');
   * // => 'abc-_-'
   */
  function trimStart(string, chars, guard) {
    string = toString(string);
    if (string && (guard || chars === undefined)) {
      return string.replace(reTrimStart, '');
    }
    if (!string || !(chars = baseToString(chars))) {
      return string;
    }
    var strSymbols = stringToArray(string),
        start = charsStartIndex(strSymbols, stringToArray(chars));

    return castSlice(strSymbols, start).join('');
  }

  /**
   * Truncates `string` if it's longer than the given maximum string length.
   * The last characters of the truncated string are replaced with the omission
   * string which defaults to "...".
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to truncate.
   * @param {Object} [options={}] The options object.
   * @param {number} [options.length=30] The maximum string length.
   * @param {string} [options.omission='...'] The string to indicate text is omitted.
   * @param {RegExp|string} [options.separator] The separator pattern to truncate to.
   * @returns {string} Returns the truncated string.
   * @example
   *
   * _.truncate('hi-diddly-ho there, neighborino');
   * // => 'hi-diddly-ho there, neighbo...'
   *
   * _.truncate('hi-diddly-ho there, neighborino', {
   *   'length': 24,
   *   'separator': ' '
   * });
   * // => 'hi-diddly-ho there,...'
   *
   * _.truncate('hi-diddly-ho there, neighborino', {
   *   'length': 24,
   *   'separator': /,? +/
   * });
   * // => 'hi-diddly-ho there...'
   *
   * _.truncate('hi-diddly-ho there, neighborino', {
   *   'omission': ' [...]'
   * });
   * // => 'hi-diddly-ho there, neig [...]'
   */
  function truncate(string, options) {
    var length = DEFAULT_TRUNC_LENGTH,
        omission = DEFAULT_TRUNC_OMISSION;

    if (isObject(options)) {
      var separator = 'separator' in options ? options.separator : separator;
      length = 'length' in options ? toInteger(options.length) : length;
      omission = 'omission' in options ? baseToString(options.omission) : omission;
    }
    string = toString(string);

    var strLength = string.length;
    if (hasUnicode(string)) {
      var strSymbols = stringToArray(string);
      strLength = strSymbols.length;
    }
    if (length >= strLength) {
      return string;
    }
    var end = length - stringSize(omission);
    if (end < 1) {
      return omission;
    }
    var result = strSymbols
      ? castSlice(strSymbols, 0, end).join('')
      : string.slice(0, end);

    if (separator === undefined) {
      return result + omission;
    }
    if (strSymbols) {
      end += (result.length - end);
    }
    if (isRegExp(separator)) {
      if (string.slice(end).search(separator)) {
        var match,
            substring = result;

        if (!separator.global) {
          separator = RegExp(separator.source, toString(reFlags.exec(separator)) + 'g');
        }
        separator.lastIndex = 0;
        while ((match = separator.exec(substring))) {
          var newEnd = match.index;
        }
        result = result.slice(0, newEnd === undefined ? end : newEnd);
      }
    } else if (string.indexOf(baseToString(separator), end) != end) {
      var index = result.lastIndexOf(separator);
      if (index > -1) {
        result = result.slice(0, index);
      }
    }
    return result + omission;
  }

  /**
   * The inverse of `_.escape`; this method converts the HTML entities
   * `&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to
   * their corresponding characters.
   *
   * **Note:** No other HTML entities are unescaped. To unescape additional
   * HTML entities use a third-party library like [_he_](https://mths.be/he).
   *
   * @static
   * @memberOf _
   * @since 0.6.0
   * @category String
   * @param {string} [string=''] The string to unescape.
   * @returns {string} Returns the unescaped string.
   * @example
   *
   * _.unescape('fred, barney, &amp; pebbles');
   * // => 'fred, barney, & pebbles'
   */
  function unescape(string) {
    string = toString(string);
    return (string && reHasEscapedHtml.test(string))
      ? string.replace(reEscapedHtml, unescapeHtmlChar)
      : string;
  }

  /**
   * Converts `string`, as space separated words, to upper case.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the upper cased string.
   * @example
   *
   * _.upperCase('--foo-bar');
   * // => 'FOO BAR'
   *
   * _.upperCase('fooBar');
   * // => 'FOO BAR'
   *
   * _.upperCase('__foo_bar__');
   * // => 'FOO BAR'
   */
  var upperCase = createCompounder(function(result, word, index) {
    return result + (index ? ' ' : '') + word.toUpperCase();
  });

  /**
   * Converts the first character of `string` to upper case.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category String
   * @param {string} [string=''] The string to convert.
   * @returns {string} Returns the converted string.
   * @example
   *
   * _.upperFirst('fred');
   * // => 'Fred'
   *
   * _.upperFirst('FRED');
   * // => 'FRED'
   */
  var upperFirst = createCaseFirst('toUpperCase');

  /**
   * Splits `string` into an array of its words.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category String
   * @param {string} [string=''] The string to inspect.
   * @param {RegExp|string} [pattern] The pattern to match words.
   * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
   * @returns {Array} Returns the words of `string`.
   * @example
   *
   * _.words('fred, barney, & pebbles');
   * // => ['fred', 'barney', 'pebbles']
   *
   * _.words('fred, barney, & pebbles', /[^, ]+/g);
   * // => ['fred', 'barney', '&', 'pebbles']
   */
  function words(string, pattern, guard) {
    string = toString(string);
    pattern = guard ? undefined : pattern;

    if (pattern === undefined) {
      return hasUnicodeWord(string) ? unicodeWords(string) : asciiWords(string);
    }
    return string.match(pattern) || [];
  }

  /*------------------------------------------------------------------------*/

  /**
   * Attempts to invoke `func`, returning either the result or the caught error
   * object. Any additional arguments are provided to `func` when it's invoked.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Util
   * @param {Function} func The function to attempt.
   * @param {...*} [args] The arguments to invoke `func` with.
   * @returns {*} Returns the `func` result or error object.
   * @example
   *
   * // Avoid throwing errors for invalid selectors.
   * var elements = _.attempt(function(selector) {
   *   return document.querySelectorAll(selector);
   * }, '>_>');
   *
   * if (_.isError(elements)) {
   *   elements = [];
   * }
   */
  var attempt = baseRest(function(func, args) {
    try {
      return apply(func, undefined, args);
    } catch (e) {
      return isError(e) ? e : new Error(e);
    }
  });

  /**
   * Binds methods of an object to the object itself, overwriting the existing
   * method.
   *
   * **Note:** This method doesn't set the "length" property of bound functions.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {Object} object The object to bind and assign the bound methods to.
   * @param {...(string|string[])} methodNames The object method names to bind.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var view = {
   *   'label': 'docs',
   *   'click': function() {
   *     console.log('clicked ' + this.label);
   *   }
   * };
   *
   * _.bindAll(view, ['click']);
   * jQuery(element).on('click', view.click);
   * // => Logs 'clicked docs' when clicked.
   */
  var bindAll = flatRest(function(object, methodNames) {
    arrayEach(methodNames, function(key) {
      key = toKey(key);
      baseAssignValue(object, key, bind(object[key], object));
    });
    return object;
  });

  /**
   * Creates a function that iterates over `pairs` and invokes the corresponding
   * function of the first predicate to return truthy. The predicate-function
   * pairs are invoked with the `this` binding and arguments of the created
   * function.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {Array} pairs The predicate-function pairs.
   * @returns {Function} Returns the new composite function.
   * @example
   *
   * var func = _.cond([
   *   [_.matches({ 'a': 1 }),           _.constant('matches A')],
   *   [_.conforms({ 'b': _.isNumber }), _.constant('matches B')],
   *   [_.stubTrue,                      _.constant('no match')]
   * ]);
   *
   * func({ 'a': 1, 'b': 2 });
   * // => 'matches A'
   *
   * func({ 'a': 0, 'b': 1 });
   * // => 'matches B'
   *
   * func({ 'a': '1', 'b': '2' });
   * // => 'no match'
   */
  function cond(pairs) {
    var length = pairs == null ? 0 : pairs.length,
        toIteratee = getIteratee();

    pairs = !length ? [] : arrayMap(pairs, function(pair) {
      if (typeof pair[1] != 'function') {
        throw new TypeError(FUNC_ERROR_TEXT);
      }
      return [toIteratee(pair[0]), pair[1]];
    });

    return baseRest(function(args) {
      var index = -1;
      while (++index < length) {
        var pair = pairs[index];
        if (apply(pair[0], this, args)) {
          return apply(pair[1], this, args);
        }
      }
    });
  }

  /**
   * Creates a function that invokes the predicate properties of `source` with
   * the corresponding property values of a given object, returning `true` if
   * all predicates return truthy, else `false`.
   *
   * **Note:** The created function is equivalent to `_.conformsTo` with
   * `source` partially applied.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {Object} source The object of property predicates to conform to.
   * @returns {Function} Returns the new spec function.
   * @example
   *
   * var objects = [
   *   { 'a': 2, 'b': 1 },
   *   { 'a': 1, 'b': 2 }
   * ];
   *
   * _.filter(objects, _.conforms({ 'b': function(n) { return n > 1; } }));
   * // => [{ 'a': 1, 'b': 2 }]
   */
  function conforms(source) {
    return baseConforms(baseClone(source, CLONE_DEEP_FLAG));
  }

  /**
   * Creates a function that returns `value`.
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Util
   * @param {*} value The value to return from the new function.
   * @returns {Function} Returns the new constant function.
   * @example
   *
   * var objects = _.times(2, _.constant({ 'a': 1 }));
   *
   * console.log(objects);
   * // => [{ 'a': 1 }, { 'a': 1 }]
   *
   * console.log(objects[0] === objects[1]);
   * // => true
   */
  function constant(value) {
    return function() {
      return value;
    };
  }

  /**
   * Checks `value` to determine whether a default value should be returned in
   * its place. The `defaultValue` is returned if `value` is `NaN`, `null`,
   * or `undefined`.
   *
   * @static
   * @memberOf _
   * @since 4.14.0
   * @category Util
   * @param {*} value The value to check.
   * @param {*} defaultValue The default value.
   * @returns {*} Returns the resolved value.
   * @example
   *
   * _.defaultTo(1, 10);
   * // => 1
   *
   * _.defaultTo(undefined, 10);
   * // => 10
   */
  function defaultTo(value, defaultValue) {
    return (value == null || value !== value) ? defaultValue : value;
  }

  /**
   * Creates a function that returns the result of invoking the given functions
   * with the `this` binding of the created function, where each successive
   * invocation is supplied the return value of the previous.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Util
   * @param {...(Function|Function[])} [funcs] The functions to invoke.
   * @returns {Function} Returns the new composite function.
   * @see _.flowRight
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var addSquare = _.flow([_.add, square]);
   * addSquare(1, 2);
   * // => 9
   */
  var flow = createFlow();

  /**
   * This method is like `_.flow` except that it creates a function that
   * invokes the given functions from right to left.
   *
   * @static
   * @since 3.0.0
   * @memberOf _
   * @category Util
   * @param {...(Function|Function[])} [funcs] The functions to invoke.
   * @returns {Function} Returns the new composite function.
   * @see _.flow
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var addSquare = _.flowRight([square, _.add]);
   * addSquare(1, 2);
   * // => 9
   */
  var flowRight = createFlow(true);

  /**
   * This method returns the first argument it receives.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {*} value Any value.
   * @returns {*} Returns `value`.
   * @example
   *
   * var object = { 'a': 1 };
   *
   * console.log(_.identity(object) === object);
   * // => true
   */
  function identity(value) {
    return value;
  }

  /**
   * Creates a function that invokes `func` with the arguments of the created
   * function. If `func` is a property name, the created function returns the
   * property value for a given element. If `func` is an array or object, the
   * created function returns `true` for elements that contain the equivalent
   * source properties, otherwise it returns `false`.
   *
   * @static
   * @since 4.0.0
   * @memberOf _
   * @category Util
   * @param {*} [func=_.identity] The value to convert to a callback.
   * @returns {Function} Returns the callback.
   * @example
   *
   * var users = [
   *   { 'user': 'barney', 'age': 36, 'active': true },
   *   { 'user': 'fred',   'age': 40, 'active': false }
   * ];
   *
   * // The `_.matches` iteratee shorthand.
   * _.filter(users, _.iteratee({ 'user': 'barney', 'active': true }));
   * // => [{ 'user': 'barney', 'age': 36, 'active': true }]
   *
   * // The `_.matchesProperty` iteratee shorthand.
   * _.filter(users, _.iteratee(['user', 'fred']));
   * // => [{ 'user': 'fred', 'age': 40 }]
   *
   * // The `_.property` iteratee shorthand.
   * _.map(users, _.iteratee('user'));
   * // => ['barney', 'fred']
   *
   * // Create custom iteratee shorthands.
   * _.iteratee = _.wrap(_.iteratee, function(iteratee, func) {
   *   return !_.isRegExp(func) ? iteratee(func) : function(string) {
   *     return func.test(string);
   *   };
   * });
   *
   * _.filter(['abc', 'def'], /ef/);
   * // => ['def']
   */
  function iteratee(func) {
    return baseIteratee(typeof func == 'function' ? func : baseClone(func, CLONE_DEEP_FLAG));
  }

  /**
   * Creates a function that performs a partial deep comparison between a given
   * object and `source`, returning `true` if the given object has equivalent
   * property values, else `false`.
   *
   * **Note:** The created function is equivalent to `_.isMatch` with `source`
   * partially applied.
   *
   * Partial comparisons will match empty array and empty object `source`
   * values against any array or object value, respectively. See `_.isEqual`
   * for a list of supported value comparisons.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Util
   * @param {Object} source The object of property values to match.
   * @returns {Function} Returns the new spec function.
   * @example
   *
   * var objects = [
   *   { 'a': 1, 'b': 2, 'c': 3 },
   *   { 'a': 4, 'b': 5, 'c': 6 }
   * ];
   *
   * _.filter(objects, _.matches({ 'a': 4, 'c': 6 }));
   * // => [{ 'a': 4, 'b': 5, 'c': 6 }]
   */
  function matches(source) {
    return baseMatches(baseClone(source, CLONE_DEEP_FLAG));
  }

  /**
   * Creates a function that performs a partial deep comparison between the
   * value at `path` of a given object to `srcValue`, returning `true` if the
   * object value is equivalent, else `false`.
   *
   * **Note:** Partial comparisons will match empty array and empty object
   * `srcValue` values against any array or object value, respectively. See
   * `_.isEqual` for a list of supported value comparisons.
   *
   * @static
   * @memberOf _
   * @since 3.2.0
   * @category Util
   * @param {Array|string} path The path of the property to get.
   * @param {*} srcValue The value to match.
   * @returns {Function} Returns the new spec function.
   * @example
   *
   * var objects = [
   *   { 'a': 1, 'b': 2, 'c': 3 },
   *   { 'a': 4, 'b': 5, 'c': 6 }
   * ];
   *
   * _.find(objects, _.matchesProperty('a', 4));
   * // => { 'a': 4, 'b': 5, 'c': 6 }
   */
  function matchesProperty(path, srcValue) {
    return baseMatchesProperty(path, baseClone(srcValue, CLONE_DEEP_FLAG));
  }

  /**
   * Creates a function that invokes the method at `path` of a given object.
   * Any additional arguments are provided to the invoked method.
   *
   * @static
   * @memberOf _
   * @since 3.7.0
   * @category Util
   * @param {Array|string} path The path of the method to invoke.
   * @param {...*} [args] The arguments to invoke the method with.
   * @returns {Function} Returns the new invoker function.
   * @example
   *
   * var objects = [
   *   { 'a': { 'b': _.constant(2) } },
   *   { 'a': { 'b': _.constant(1) } }
   * ];
   *
   * _.map(objects, _.method('a.b'));
   * // => [2, 1]
   *
   * _.map(objects, _.method(['a', 'b']));
   * // => [2, 1]
   */
  var method = baseRest(function(path, args) {
    return function(object) {
      return baseInvoke(object, path, args);
    };
  });

  /**
   * The opposite of `_.method`; this method creates a function that invokes
   * the method at a given path of `object`. Any additional arguments are
   * provided to the invoked method.
   *
   * @static
   * @memberOf _
   * @since 3.7.0
   * @category Util
   * @param {Object} object The object to query.
   * @param {...*} [args] The arguments to invoke the method with.
   * @returns {Function} Returns the new invoker function.
   * @example
   *
   * var array = _.times(3, _.constant),
   *     object = { 'a': array, 'b': array, 'c': array };
   *
   * _.map(['a[2]', 'c[0]'], _.methodOf(object));
   * // => [2, 0]
   *
   * _.map([['a', '2'], ['c', '0']], _.methodOf(object));
   * // => [2, 0]
   */
  var methodOf = baseRest(function(object, args) {
    return function(path) {
      return baseInvoke(object, path, args);
    };
  });

  /**
   * Adds all own enumerable string keyed function properties of a source
   * object to the destination object. If `object` is a function, then methods
   * are added to its prototype as well.
   *
   * **Note:** Use `_.runInContext` to create a pristine `lodash` function to
   * avoid conflicts caused by modifying the original.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {Function|Object} [object=lodash] The destination object.
   * @param {Object} source The object of functions to add.
   * @param {Object} [options={}] The options object.
   * @param {boolean} [options.chain=true] Specify whether mixins are chainable.
   * @returns {Function|Object} Returns `object`.
   * @example
   *
   * function vowels(string) {
   *   return _.filter(string, function(v) {
   *     return /[aeiou]/i.test(v);
   *   });
   * }
   *
   * _.mixin({ 'vowels': vowels });
   * _.vowels('fred');
   * // => ['e']
   *
   * _('fred').vowels().value();
   * // => ['e']
   *
   * _.mixin({ 'vowels': vowels }, { 'chain': false });
   * _('fred').vowels();
   * // => ['e']
   */
  function mixin(object, source, options) {
    var props = keys(source),
        methodNames = baseFunctions(source, props);

    if (options == null &&
        !(isObject(source) && (methodNames.length || !props.length))) {
      options = source;
      source = object;
      object = this;
      methodNames = baseFunctions(source, keys(source));
    }
    var chain = !(isObject(options) && 'chain' in options) || !!options.chain,
        isFunc = isFunction(object);

    arrayEach(methodNames, function(methodName) {
      var func = source[methodName];
      object[methodName] = func;
      if (isFunc) {
        object.prototype[methodName] = function() {
          var chainAll = this.__chain__;
          if (chain || chainAll) {
            var result = object(this.__wrapped__),
                actions = result.__actions__ = copyArray(this.__actions__);

            actions.push({ 'func': func, 'args': arguments, 'thisArg': object });
            result.__chain__ = chainAll;
            return result;
          }
          return func.apply(object, arrayPush([this.value()], arguments));
        };
      }
    });

    return object;
  }

  /**
   * Reverts the `_` variable to its previous value and returns a reference to
   * the `lodash` function.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @returns {Function} Returns the `lodash` function.
   * @example
   *
   * var lodash = _.noConflict();
   */
  function noConflict() {
    if (root._ === this) {
      root._ = oldDash;
    }
    return this;
  }

  /**
   * This method returns `undefined`.
   *
   * @static
   * @memberOf _
   * @since 2.3.0
   * @category Util
   * @example
   *
   * _.times(2, _.noop);
   * // => [undefined, undefined]
   */
  function noop() {
    // No operation performed.
  }

  /**
   * Creates a function that gets the argument at index `n`. If `n` is negative,
   * the nth argument from the end is returned.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {number} [n=0] The index of the argument to return.
   * @returns {Function} Returns the new pass-thru function.
   * @example
   *
   * var func = _.nthArg(1);
   * func('a', 'b', 'c', 'd');
   * // => 'b'
   *
   * var func = _.nthArg(-2);
   * func('a', 'b', 'c', 'd');
   * // => 'c'
   */
  function nthArg(n) {
    n = toInteger(n);
    return baseRest(function(args) {
      return baseNth(args, n);
    });
  }

  /**
   * Creates a function that invokes `iteratees` with the arguments it receives
   * and returns their results.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {...(Function|Function[])} [iteratees=[_.identity]]
   *  The iteratees to invoke.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var func = _.over([Math.max, Math.min]);
   *
   * func(1, 2, 3, 4);
   * // => [4, 1]
   */
  var over = createOver(arrayMap);

  /**
   * Creates a function that checks if **all** of the `predicates` return
   * truthy when invoked with the arguments it receives.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {...(Function|Function[])} [predicates=[_.identity]]
   *  The predicates to check.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var func = _.overEvery([Boolean, isFinite]);
   *
   * func('1');
   * // => true
   *
   * func(null);
   * // => false
   *
   * func(NaN);
   * // => false
   */
  var overEvery = createOver(arrayEvery);

  /**
   * Creates a function that checks if **any** of the `predicates` return
   * truthy when invoked with the arguments it receives.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {...(Function|Function[])} [predicates=[_.identity]]
   *  The predicates to check.
   * @returns {Function} Returns the new function.
   * @example
   *
   * var func = _.overSome([Boolean, isFinite]);
   *
   * func('1');
   * // => true
   *
   * func(null);
   * // => true
   *
   * func(NaN);
   * // => false
   */
  var overSome = createOver(arraySome);

  /**
   * Creates a function that returns the value at `path` of a given object.
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Util
   * @param {Array|string} path The path of the property to get.
   * @returns {Function} Returns the new accessor function.
   * @example
   *
   * var objects = [
   *   { 'a': { 'b': 2 } },
   *   { 'a': { 'b': 1 } }
   * ];
   *
   * _.map(objects, _.property('a.b'));
   * // => [2, 1]
   *
   * _.map(_.sortBy(objects, _.property(['a', 'b'])), 'a.b');
   * // => [1, 2]
   */
  function property(path) {
    return isKey(path) ? baseProperty(toKey(path)) : basePropertyDeep(path);
  }

  /**
   * The opposite of `_.property`; this method creates a function that returns
   * the value at a given path of `object`.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Util
   * @param {Object} object The object to query.
   * @returns {Function} Returns the new accessor function.
   * @example
   *
   * var array = [0, 1, 2],
   *     object = { 'a': array, 'b': array, 'c': array };
   *
   * _.map(['a[2]', 'c[0]'], _.propertyOf(object));
   * // => [2, 0]
   *
   * _.map([['a', '2'], ['c', '0']], _.propertyOf(object));
   * // => [2, 0]
   */
  function propertyOf(object) {
    return function(path) {
      return object == null ? undefined : baseGet(object, path);
    };
  }

  /**
   * Creates an array of numbers (positive and/or negative) progressing from
   * `start` up to, but not including, `end`. A step of `-1` is used if a negative
   * `start` is specified without an `end` or `step`. If `end` is not specified,
   * it's set to `start` with `start` then set to `0`.
   *
   * **Note:** JavaScript follows the IEEE-754 standard for resolving
   * floating-point values which can produce unexpected results.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {number} [start=0] The start of the range.
   * @param {number} end The end of the range.
   * @param {number} [step=1] The value to increment or decrement by.
   * @returns {Array} Returns the range of numbers.
   * @see _.inRange, _.rangeRight
   * @example
   *
   * _.range(4);
   * // => [0, 1, 2, 3]
   *
   * _.range(-4);
   * // => [0, -1, -2, -3]
   *
   * _.range(1, 5);
   * // => [1, 2, 3, 4]
   *
   * _.range(0, 20, 5);
   * // => [0, 5, 10, 15]
   *
   * _.range(0, -4, -1);
   * // => [0, -1, -2, -3]
   *
   * _.range(1, 4, 0);
   * // => [1, 1, 1]
   *
   * _.range(0);
   * // => []
   */
  var range = createRange();

  /**
   * This method is like `_.range` except that it populates values in
   * descending order.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {number} [start=0] The start of the range.
   * @param {number} end The end of the range.
   * @param {number} [step=1] The value to increment or decrement by.
   * @returns {Array} Returns the range of numbers.
   * @see _.inRange, _.range
   * @example
   *
   * _.rangeRight(4);
   * // => [3, 2, 1, 0]
   *
   * _.rangeRight(-4);
   * // => [-3, -2, -1, 0]
   *
   * _.rangeRight(1, 5);
   * // => [4, 3, 2, 1]
   *
   * _.rangeRight(0, 20, 5);
   * // => [15, 10, 5, 0]
   *
   * _.rangeRight(0, -4, -1);
   * // => [-3, -2, -1, 0]
   *
   * _.rangeRight(1, 4, 0);
   * // => [1, 1, 1]
   *
   * _.rangeRight(0);
   * // => []
   */
  var rangeRight = createRange(true);

  /**
   * This method returns a new empty array.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {Array} Returns the new empty array.
   * @example
   *
   * var arrays = _.times(2, _.stubArray);
   *
   * console.log(arrays);
   * // => [[], []]
   *
   * console.log(arrays[0] === arrays[1]);
   * // => false
   */
  function stubArray() {
    return [];
  }

  /**
   * This method returns `false`.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {boolean} Returns `false`.
   * @example
   *
   * _.times(2, _.stubFalse);
   * // => [false, false]
   */
  function stubFalse() {
    return false;
  }

  /**
   * This method returns a new empty object.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {Object} Returns the new empty object.
   * @example
   *
   * var objects = _.times(2, _.stubObject);
   *
   * console.log(objects);
   * // => [{}, {}]
   *
   * console.log(objects[0] === objects[1]);
   * // => false
   */
  function stubObject() {
    return {};
  }

  /**
   * This method returns an empty string.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {string} Returns the empty string.
   * @example
   *
   * _.times(2, _.stubString);
   * // => ['', '']
   */
  function stubString() {
    return '';
  }

  /**
   * This method returns `true`.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {boolean} Returns `true`.
   * @example
   *
   * _.times(2, _.stubTrue);
   * // => [true, true]
   */
  function stubTrue() {
    return true;
  }

  /**
   * Invokes the iteratee `n` times, returning an array of the results of
   * each invocation. The iteratee is invoked with one argument; (index).
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {number} n The number of times to invoke `iteratee`.
   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
   * @returns {Array} Returns the array of results.
   * @example
   *
   * _.times(3, String);
   * // => ['0', '1', '2']
   *
   *  _.times(4, _.constant(0));
   * // => [0, 0, 0, 0]
   */
  function times(n, iteratee) {
    n = toInteger(n);
    if (n < 1 || n > MAX_SAFE_INTEGER) {
      return [];
    }
    var index = MAX_ARRAY_LENGTH,
        length = nativeMin(n, MAX_ARRAY_LENGTH);

    iteratee = getIteratee(iteratee);
    n -= MAX_ARRAY_LENGTH;

    var result = baseTimes(length, iteratee);
    while (++index < n) {
      iteratee(index);
    }
    return result;
  }

  /**
   * Converts `value` to a property path array.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Util
   * @param {*} value The value to convert.
   * @returns {Array} Returns the new property path array.
   * @example
   *
   * _.toPath('a.b.c');
   * // => ['a', 'b', 'c']
   *
   * _.toPath('a[0].b.c');
   * // => ['a', '0', 'b', 'c']
   */
  function toPath(value) {
    if (isArray(value)) {
      return arrayMap(value, toKey);
    }
    return isSymbol(value) ? [value] : copyArray(stringToPath(toString(value)));
  }

  /**
   * Generates a unique ID. If `prefix` is given, the ID is appended to it.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Util
   * @param {string} [prefix=''] The value to prefix the ID with.
   * @returns {string} Returns the unique ID.
   * @example
   *
   * _.uniqueId('contact_');
   * // => 'contact_104'
   *
   * _.uniqueId();
   * // => '105'
   */
  function uniqueId(prefix) {
    var id = ++idCounter;
    return toString(prefix) + id;
  }

  /*------------------------------------------------------------------------*/

  /**
   * Adds two numbers.
   *
   * @static
   * @memberOf _
   * @since 3.4.0
   * @category Math
   * @param {number} augend The first number in an addition.
   * @param {number} addend The second number in an addition.
   * @returns {number} Returns the total.
   * @example
   *
   * _.add(6, 4);
   * // => 10
   */
  var add = createMathOperation(function(augend, addend) {
    return augend + addend;
  }, 0);

  /**
   * Computes `number` rounded up to `precision`.
   *
   * @static
   * @memberOf _
   * @since 3.10.0
   * @category Math
   * @param {number} number The number to round up.
   * @param {number} [precision=0] The precision to round up to.
   * @returns {number} Returns the rounded up number.
   * @example
   *
   * _.ceil(4.006);
   * // => 5
   *
   * _.ceil(6.004, 2);
   * // => 6.01
   *
   * _.ceil(6040, -2);
   * // => 6100
   */
  var ceil = createRound('ceil');

  /**
   * Divide two numbers.
   *
   * @static
   * @memberOf _
   * @since 4.7.0
   * @category Math
   * @param {number} dividend The first number in a division.
   * @param {number} divisor The second number in a division.
   * @returns {number} Returns the quotient.
   * @example
   *
   * _.divide(6, 4);
   * // => 1.5
   */
  var divide = createMathOperation(function(dividend, divisor) {
    return dividend / divisor;
  }, 1);

  /**
   * Computes `number` rounded down to `precision`.
   *
   * @static
   * @memberOf _
   * @since 3.10.0
   * @category Math
   * @param {number} number The number to round down.
   * @param {number} [precision=0] The precision to round down to.
   * @returns {number} Returns the rounded down number.
   * @example
   *
   * _.floor(4.006);
   * // => 4
   *
   * _.floor(0.046, 2);
   * // => 0.04
   *
   * _.floor(4060, -2);
   * // => 4000
   */
  var floor = createRound('floor');

  /**
   * Computes the maximum value of `array`. If `array` is empty or falsey,
   * `undefined` is returned.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Math
   * @param {Array} array The array to iterate over.
   * @returns {*} Returns the maximum value.
   * @example
   *
   * _.max([4, 2, 8, 6]);
   * // => 8
   *
   * _.max([]);
   * // => undefined
   */
  function max(array) {
    return (array && array.length)
      ? baseExtremum(array, identity, baseGt)
      : undefined;
  }

  /**
   * This method is like `_.max` except that it accepts `iteratee` which is
   * invoked for each element in `array` to generate the criterion by which
   * the value is ranked. The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {*} Returns the maximum value.
   * @example
   *
   * var objects = [{ 'n': 1 }, { 'n': 2 }];
   *
   * _.maxBy(objects, function(o) { return o.n; });
   * // => { 'n': 2 }
   *
   * // The `_.property` iteratee shorthand.
   * _.maxBy(objects, 'n');
   * // => { 'n': 2 }
   */
  function maxBy(array, iteratee) {
    return (array && array.length)
      ? baseExtremum(array, getIteratee(iteratee, 2), baseGt)
      : undefined;
  }

  /**
   * Computes the mean of the values in `array`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @returns {number} Returns the mean.
   * @example
   *
   * _.mean([4, 2, 8, 6]);
   * // => 5
   */
  function mean(array) {
    return baseMean(array, identity);
  }

  /**
   * This method is like `_.mean` except that it accepts `iteratee` which is
   * invoked for each element in `array` to generate the value to be averaged.
   * The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.7.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {number} Returns the mean.
   * @example
   *
   * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
   *
   * _.meanBy(objects, function(o) { return o.n; });
   * // => 5
   *
   * // The `_.property` iteratee shorthand.
   * _.meanBy(objects, 'n');
   * // => 5
   */
  function meanBy(array, iteratee) {
    return baseMean(array, getIteratee(iteratee, 2));
  }

  /**
   * Computes the minimum value of `array`. If `array` is empty or falsey,
   * `undefined` is returned.
   *
   * @static
   * @since 0.1.0
   * @memberOf _
   * @category Math
   * @param {Array} array The array to iterate over.
   * @returns {*} Returns the minimum value.
   * @example
   *
   * _.min([4, 2, 8, 6]);
   * // => 2
   *
   * _.min([]);
   * // => undefined
   */
  function min(array) {
    return (array && array.length)
      ? baseExtremum(array, identity, baseLt)
      : undefined;
  }

  /**
   * This method is like `_.min` except that it accepts `iteratee` which is
   * invoked for each element in `array` to generate the criterion by which
   * the value is ranked. The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {*} Returns the minimum value.
   * @example
   *
   * var objects = [{ 'n': 1 }, { 'n': 2 }];
   *
   * _.minBy(objects, function(o) { return o.n; });
   * // => { 'n': 1 }
   *
   * // The `_.property` iteratee shorthand.
   * _.minBy(objects, 'n');
   * // => { 'n': 1 }
   */
  function minBy(array, iteratee) {
    return (array && array.length)
      ? baseExtremum(array, getIteratee(iteratee, 2), baseLt)
      : undefined;
  }

  /**
   * Multiply two numbers.
   *
   * @static
   * @memberOf _
   * @since 4.7.0
   * @category Math
   * @param {number} multiplier The first number in a multiplication.
   * @param {number} multiplicand The second number in a multiplication.
   * @returns {number} Returns the product.
   * @example
   *
   * _.multiply(6, 4);
   * // => 24
   */
  var multiply = createMathOperation(function(multiplier, multiplicand) {
    return multiplier * multiplicand;
  }, 1);

  /**
   * Computes `number` rounded to `precision`.
   *
   * @static
   * @memberOf _
   * @since 3.10.0
   * @category Math
   * @param {number} number The number to round.
   * @param {number} [precision=0] The precision to round to.
   * @returns {number} Returns the rounded number.
   * @example
   *
   * _.round(4.006);
   * // => 4
   *
   * _.round(4.006, 2);
   * // => 4.01
   *
   * _.round(4060, -2);
   * // => 4100
   */
  var round = createRound('round');

  /**
   * Subtract two numbers.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Math
   * @param {number} minuend The first number in a subtraction.
   * @param {number} subtrahend The second number in a subtraction.
   * @returns {number} Returns the difference.
   * @example
   *
   * _.subtract(6, 4);
   * // => 2
   */
  var subtract = createMathOperation(function(minuend, subtrahend) {
    return minuend - subtrahend;
  }, 0);

  /**
   * Computes the sum of the values in `array`.
   *
   * @static
   * @memberOf _
   * @since 3.4.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @returns {number} Returns the sum.
   * @example
   *
   * _.sum([4, 2, 8, 6]);
   * // => 20
   */
  function sum(array) {
    return (array && array.length)
      ? baseSum(array, identity)
      : 0;
  }

  /**
   * This method is like `_.sum` except that it accepts `iteratee` which is
   * invoked for each element in `array` to generate the value to be summed.
   * The iteratee is invoked with one argument: (value).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Math
   * @param {Array} array The array to iterate over.
   * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
   * @returns {number} Returns the sum.
   * @example
   *
   * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
   *
   * _.sumBy(objects, function(o) { return o.n; });
   * // => 20
   *
   * // The `_.property` iteratee shorthand.
   * _.sumBy(objects, 'n');
   * // => 20
   */
  function sumBy(array, iteratee) {
    return (array && array.length)
      ? baseSum(array, getIteratee(iteratee, 2))
      : 0;
  }

  /*------------------------------------------------------------------------*/

  // Add methods that return wrapped values in chain sequences.
  lodash.after = after;
  lodash.ary = ary;
  lodash.assign = assign;
  lodash.assignIn = assignIn;
  lodash.assignInWith = assignInWith;
  lodash.assignWith = assignWith;
  lodash.at = at;
  lodash.before = before;
  lodash.bind = bind;
  lodash.bindAll = bindAll;
  lodash.bindKey = bindKey;
  lodash.castArray = castArray;
  lodash.chain = chain;
  lodash.chunk = chunk;
  lodash.compact = compact;
  lodash.concat = concat;
  lodash.cond = cond;
  lodash.conforms = conforms;
  lodash.constant = constant;
  lodash.countBy = countBy;
  lodash.create = create;
  lodash.curry = curry;
  lodash.curryRight = curryRight;
  lodash.debounce = debounce;
  lodash.defaults = defaults;
  lodash.defaultsDeep = defaultsDeep;
  lodash.defer = defer;
  lodash.delay = delay;
  lodash.difference = difference;
  lodash.differenceBy = differenceBy;
  lodash.differenceWith = differenceWith;
  lodash.drop = drop;
  lodash.dropRight = dropRight;
  lodash.dropRightWhile = dropRightWhile;
  lodash.dropWhile = dropWhile;
  lodash.fill = fill;
  lodash.filter = filter;
  lodash.flatMap = flatMap;
  lodash.flatMapDeep = flatMapDeep;
  lodash.flatMapDepth = flatMapDepth;
  lodash.flatten = flatten;
  lodash.flattenDeep = flattenDeep;
  lodash.flattenDepth = flattenDepth;
  lodash.flip = flip;
  lodash.flow = flow;
  lodash.flowRight = flowRight;
  lodash.fromPairs = fromPairs;
  lodash.functions = functions;
  lodash.functionsIn = functionsIn;
  lodash.groupBy = groupBy;
  lodash.initial = initial;
  lodash.intersection = intersection;
  lodash.intersectionBy = intersectionBy;
  lodash.intersectionWith = intersectionWith;
  lodash.invert = invert;
  lodash.invertBy = invertBy;
  lodash.invokeMap = invokeMap;
  lodash.iteratee = iteratee;
  lodash.keyBy = keyBy;
  lodash.keys = keys;
  lodash.keysIn = keysIn;
  lodash.map = map;
  lodash.mapKeys = mapKeys;
  lodash.mapValues = mapValues;
  lodash.matches = matches;
  lodash.matchesProperty = matchesProperty;
  lodash.memoize = memoize;
  lodash.merge = merge;
  lodash.mergeWith = mergeWith;
  lodash.method = method;
  lodash.methodOf = methodOf;
  lodash.mixin = mixin;
  lodash.negate = negate;
  lodash.nthArg = nthArg;
  lodash.omit = omit;
  lodash.omitBy = omitBy;
  lodash.once = once;
  lodash.orderBy = orderBy;
  lodash.over = over;
  lodash.overArgs = overArgs;
  lodash.overEvery = overEvery;
  lodash.overSome = overSome;
  lodash.partial = partial;
  lodash.partialRight = partialRight;
  lodash.partition = partition;
  lodash.pick = pick;
  lodash.pickBy = pickBy;
  lodash.property = property;
  lodash.propertyOf = propertyOf;
  lodash.pull = pull;
  lodash.pullAll = pullAll;
  lodash.pullAllBy = pullAllBy;
  lodash.pullAllWith = pullAllWith;
  lodash.pullAt = pullAt;
  lodash.range = range;
  lodash.rangeRight = rangeRight;
  lodash.rearg = rearg;
  lodash.reject = reject;
  lodash.remove = remove;
  lodash.rest = rest;
  lodash.reverse = reverse;
  lodash.sampleSize = sampleSize;
  lodash.set = set;
  lodash.setWith = setWith;
  lodash.shuffle = shuffle;
  lodash.slice = slice;
  lodash.sortBy = sortBy;
  lodash.sortedUniq = sortedUniq;
  lodash.sortedUniqBy = sortedUniqBy;
  lodash.split = split;
  lodash.spread = spread;
  lodash.tail = tail;
  lodash.take = take;
  lodash.takeRight = takeRight;
  lodash.takeRightWhile = takeRightWhile;
  lodash.takeWhile = takeWhile;
  lodash.tap = tap;
  lodash.throttle = throttle;
  lodash.thru = thru;
  lodash.toArray = toArray;
  lodash.toPairs = toPairs;
  lodash.toPairsIn = toPairsIn;
  lodash.toPath = toPath;
  lodash.toPlainObject = toPlainObject;
  lodash.transform = transform;
  lodash.unary = unary;
  lodash.union = union;
  lodash.unionBy = unionBy;
  lodash.unionWith = unionWith;
  lodash.uniq = uniq;
  lodash.uniqBy = uniqBy;
  lodash.uniqWith = uniqWith;
  lodash.unset = unset;
  lodash.unzip = unzip;
  lodash.unzipWith = unzipWith;
  lodash.update = update;
  lodash.updateWith = updateWith;
  lodash.values = values;
  lodash.valuesIn = valuesIn;
  lodash.without = without;
  lodash.words = words;
  lodash.wrap = wrap;
  lodash.xor = xor;
  lodash.xorBy = xorBy;
  lodash.xorWith = xorWith;
  lodash.zip = zip;
  lodash.zipObject = zipObject;
  lodash.zipObjectDeep = zipObjectDeep;
  lodash.zipWith = zipWith;

  // Add aliases.
  lodash.entries = toPairs;
  lodash.entriesIn = toPairsIn;
  lodash.extend = assignIn;
  lodash.extendWith = assignInWith;

  // Add methods to `lodash.prototype`.
  mixin(lodash, lodash);

  /*------------------------------------------------------------------------*/

  // Add methods that return unwrapped values in chain sequences.
  lodash.add = add;
  lodash.attempt = attempt;
  lodash.camelCase = camelCase;
  lodash.capitalize = capitalize;
  lodash.ceil = ceil;
  lodash.clamp = clamp;
  lodash.clone = clone;
  lodash.cloneDeep = cloneDeep;
  lodash.cloneDeepWith = cloneDeepWith;
  lodash.cloneWith = cloneWith;
  lodash.conformsTo = conformsTo;
  lodash.deburr = deburr;
  lodash.defaultTo = defaultTo;
  lodash.divide = divide;
  lodash.endsWith = endsWith;
  lodash.eq = eq;
  lodash.escape = escape;
  lodash.escapeRegExp = escapeRegExp;
  lodash.every = every;
  lodash.find = find;
  lodash.findIndex = findIndex;
  lodash.findKey = findKey;
  lodash.findLast = findLast;
  lodash.findLastIndex = findLastIndex;
  lodash.findLastKey = findLastKey;
  lodash.floor = floor;
  lodash.forEach = forEach;
  lodash.forEachRight = forEachRight;
  lodash.forIn = forIn;
  lodash.forInRight = forInRight;
  lodash.forOwn = forOwn;
  lodash.forOwnRight = forOwnRight;
  lodash.get = get;
  lodash.gt = gt;
  lodash.gte = gte;
  lodash.has = has;
  lodash.hasIn = hasIn;
  lodash.head = head;
  lodash.identity = identity;
  lodash.includes = includes;
  lodash.indexOf = indexOf;
  lodash.inRange = inRange;
  lodash.invoke = invoke;
  lodash.isArguments = isArguments;
  lodash.isArray = isArray;
  lodash.isArrayBuffer = isArrayBuffer;
  lodash.isArrayLike = isArrayLike;
  lodash.isArrayLikeObject = isArrayLikeObject;
  lodash.isBoolean = isBoolean;
  lodash.isBuffer = isBuffer;
  lodash.isDate = isDate;
  lodash.isElement = isElement;
  lodash.isEmpty = isEmpty;
  lodash.isEqual = isEqual;
  lodash.isEqualWith = isEqualWith;
  lodash.isError = isError;
  lodash.isFinite = isFinite;
  lodash.isFunction = isFunction;
  lodash.isInteger = isInteger;
  lodash.isLength = isLength;
  lodash.isMap = isMap;
  lodash.isMatch = isMatch;
  lodash.isMatchWith = isMatchWith;
  lodash.isNaN = isNaN;
  lodash.isNative = isNative;
  lodash.isNil = isNil;
  lodash.isNull = isNull;
  lodash.isNumber = isNumber;
  lodash.isObject = isObject;
  lodash.isObjectLike = isObjectLike;
  lodash.isPlainObject = isPlainObject;
  lodash.isRegExp = isRegExp;
  lodash.isSafeInteger = isSafeInteger;
  lodash.isSet = isSet;
  lodash.isString = isString;
  lodash.isSymbol = isSymbol;
  lodash.isTypedArray = isTypedArray;
  lodash.isUndefined = isUndefined;
  lodash.isWeakMap = isWeakMap;
  lodash.isWeakSet = isWeakSet;
  lodash.join = join;
  lodash.kebabCase = kebabCase;
  lodash.last = last;
  lodash.lastIndexOf = lastIndexOf;
  lodash.lowerCase = lowerCase;
  lodash.lowerFirst = lowerFirst;
  lodash.lt = lt;
  lodash.lte = lte;
  lodash.max = max;
  lodash.maxBy = maxBy;
  lodash.mean = mean;
  lodash.meanBy = meanBy;
  lodash.min = min;
  lodash.minBy = minBy;
  lodash.stubArray = stubArray;
  lodash.stubFalse = stubFalse;
  lodash.stubObject = stubObject;
  lodash.stubString = stubString;
  lodash.stubTrue = stubTrue;
  lodash.multiply = multiply;
  lodash.nth = nth;
  lodash.noConflict = noConflict;
  lodash.noop = noop;
  lodash.now = now;
  lodash.pad = pad;
  lodash.padEnd = padEnd;
  lodash.padStart = padStart;
  lodash.parseInt = parseInt;
  lodash.random = random;
  lodash.reduce = reduce;
  lodash.reduceRight = reduceRight;
  lodash.repeat = repeat;
  lodash.replace = replace;
  lodash.result = result;
  lodash.round = round;
  lodash.runInContext = runInContext;
  lodash.sample = sample;
  lodash.size = size;
  lodash.snakeCase = snakeCase;
  lodash.some = some;
  lodash.sortedIndex = sortedIndex;
  lodash.sortedIndexBy = sortedIndexBy;
  lodash.sortedIndexOf = sortedIndexOf;
  lodash.sortedLastIndex = sortedLastIndex;
  lodash.sortedLastIndexBy = sortedLastIndexBy;
  lodash.sortedLastIndexOf = sortedLastIndexOf;
  lodash.startCase = startCase;
  lodash.startsWith = startsWith;
  lodash.subtract = subtract;
  lodash.sum = sum;
  lodash.sumBy = sumBy;
  lodash.template = template;
  lodash.times = times;
  lodash.toFinite = toFinite;
  lodash.toInteger = toInteger;
  lodash.toLength = toLength;
  lodash.toLower = toLower;
  lodash.toNumber = toNumber;
  lodash.toSafeInteger = toSafeInteger;
  lodash.toString = toString;
  lodash.toUpper = toUpper;
  lodash.trim = trim;
  lodash.trimEnd = trimEnd;
  lodash.trimStart = trimStart;
  lodash.truncate = truncate;
  lodash.unescape = unescape;
  lodash.uniqueId = uniqueId;
  lodash.upperCase = upperCase;
  lodash.upperFirst = upperFirst;

  // Add aliases.
  lodash.each = forEach;
  lodash.eachRight = forEachRight;
  lodash.first = head;

  mixin(lodash, (function() {
    var source = {};
    baseForOwn(lodash, function(func, methodName) {
      if (!hasOwnProperty.call(lodash.prototype, methodName)) {
        source[methodName] = func;
      }
    });
    return source;
  }()), { 'chain': false });

  /*------------------------------------------------------------------------*/

  /**
   * The semantic version number.
   *
   * @static
   * @memberOf _
   * @type {string}
   */
  lodash.VERSION = VERSION;

  // Assign default placeholders.
  arrayEach(['bind', 'bindKey', 'curry', 'curryRight', 'partial', 'partialRight'], function(methodName) {
    lodash[methodName].placeholder = lodash;
  });

  // Add `LazyWrapper` methods for `_.drop` and `_.take` variants.
  arrayEach(['drop', 'take'], function(methodName, index) {
    LazyWrapper.prototype[methodName] = function(n) {
      n = n === undefined ? 1 : nativeMax(toInteger(n), 0);

      var result = (this.__filtered__ && !index)
        ? new LazyWrapper(this)
        : this.clone();

      if (result.__filtered__) {
        result.__takeCount__ = nativeMin(n, result.__takeCount__);
      } else {
        result.__views__.push({
          'size': nativeMin(n, MAX_ARRAY_LENGTH),
          'type': methodName + (result.__dir__ < 0 ? 'Right' : '')
        });
      }
      return result;
    };

    LazyWrapper.prototype[methodName + 'Right'] = function(n) {
      return this.reverse()[methodName](n).reverse();
    };
  });

  // Add `LazyWrapper` methods that accept an `iteratee` value.
  arrayEach(['filter', 'map', 'takeWhile'], function(methodName, index) {
    var type = index + 1,
        isFilter = type == LAZY_FILTER_FLAG || type == LAZY_WHILE_FLAG;

    LazyWrapper.prototype[methodName] = function(iteratee) {
      var result = this.clone();
      result.__iteratees__.push({
        'iteratee': getIteratee(iteratee, 3),
        'type': type
      });
      result.__filtered__ = result.__filtered__ || isFilter;
      return result;
    };
  });

  // Add `LazyWrapper` methods for `_.head` and `_.last`.
  arrayEach(['head', 'last'], function(methodName, index) {
    var takeName = 'take' + (index ? 'Right' : '');

    LazyWrapper.prototype[methodName] = function() {
      return this[takeName](1).value()[0];
    };
  });

  // Add `LazyWrapper` methods for `_.initial` and `_.tail`.
  arrayEach(['initial', 'tail'], function(methodName, index) {
    var dropName = 'drop' + (index ? '' : 'Right');

    LazyWrapper.prototype[methodName] = function() {
      return this.__filtered__ ? new LazyWrapper(this) : this[dropName](1);
    };
  });

  LazyWrapper.prototype.compact = function() {
    return this.filter(identity);
  };

  LazyWrapper.prototype.find = function(predicate) {
    return this.filter(predicate).head();
  };

  LazyWrapper.prototype.findLast = function(predicate) {
    return this.reverse().find(predicate);
  };

  LazyWrapper.prototype.invokeMap = baseRest(function(path, args) {
    if (typeof path == 'function') {
      return new LazyWrapper(this);
    }
    return this.map(function(value) {
      return baseInvoke(value, path, args);
    });
  });

  LazyWrapper.prototype.reject = function(predicate) {
    return this.filter(negate(getIteratee(predicate)));
  };

  LazyWrapper.prototype.slice = function(start, end) {
    start = toInteger(start);

    var result = this;
    if (result.__filtered__ && (start > 0 || end < 0)) {
      return new LazyWrapper(result);
    }
    if (start < 0) {
      result = result.takeRight(-start);
    } else if (start) {
      result = result.drop(start);
    }
    if (end !== undefined) {
      end = toInteger(end);
      result = end < 0 ? result.dropRight(-end) : result.take(end - start);
    }
    return result;
  };

  LazyWrapper.prototype.takeRightWhile = function(predicate) {
    return this.reverse().takeWhile(predicate).reverse();
  };

  LazyWrapper.prototype.toArray = function() {
    return this.take(MAX_ARRAY_LENGTH);
  };

  // Add `LazyWrapper` methods to `lodash.prototype`.
  baseForOwn(LazyWrapper.prototype, function(func, methodName) {
    var checkIteratee = /^(?:filter|find|map|reject)|While$/.test(methodName),
        isTaker = /^(?:head|last)$/.test(methodName),
        lodashFunc = lodash[isTaker ? ('take' + (methodName == 'last' ? 'Right' : '')) : methodName],
        retUnwrapped = isTaker || /^find/.test(methodName);

    if (!lodashFunc) {
      return;
    }
    lodash.prototype[methodName] = function() {
      var value = this.__wrapped__,
          args = isTaker ? [1] : arguments,
          isLazy = value instanceof LazyWrapper,
          iteratee = args[0],
          useLazy = isLazy || isArray(value);

      var interceptor = function(value) {
        var result = lodashFunc.apply(lodash, arrayPush([value], args));
        return (isTaker && chainAll) ? result[0] : result;
      };

      if (useLazy && checkIteratee && typeof iteratee == 'function' && iteratee.length != 1) {
        // Avoid lazy use if the iteratee has a "length" value other than `1`.
        isLazy = useLazy = false;
      }
      var chainAll = this.__chain__,
          isHybrid = !!this.__actions__.length,
          isUnwrapped = retUnwrapped && !chainAll,
          onlyLazy = isLazy && !isHybrid;

      if (!retUnwrapped && useLazy) {
        value = onlyLazy ? value : new LazyWrapper(this);
        var result = func.apply(value, args);
        result.__actions__.push({ 'func': thru, 'args': [interceptor], 'thisArg': undefined });
        return new LodashWrapper(result, chainAll);
      }
      if (isUnwrapped && onlyLazy) {
        return func.apply(this, args);
      }
      result = this.thru(interceptor);
      return isUnwrapped ? (isTaker ? result.value()[0] : result.value()) : result;
    };
  });

  // Add `Array` methods to `lodash.prototype`.
  arrayEach(['pop', 'push', 'shift', 'sort', 'splice', 'unshift'], function(methodName) {
    var func = arrayProto[methodName],
        chainName = /^(?:push|sort|unshift)$/.test(methodName) ? 'tap' : 'thru',
        retUnwrapped = /^(?:pop|shift)$/.test(methodName);

    lodash.prototype[methodName] = function() {
      var args = arguments;
      if (retUnwrapped && !this.__chain__) {
        var value = this.value();
        return func.apply(isArray(value) ? value : [], args);
      }
      return this[chainName](function(value) {
        return func.apply(isArray(value) ? value : [], args);
      });
    };
  });

  // Map minified method names to their real names.
  baseForOwn(LazyWrapper.prototype, function(func, methodName) {
    var lodashFunc = lodash[methodName];
    if (lodashFunc) {
      var key = lodashFunc.name + '';
      if (!hasOwnProperty.call(realNames, key)) {
        realNames[key] = [];
      }
      realNames[key].push({ 'name': methodName, 'func': lodashFunc });
    }
  });

  realNames[createHybrid(undefined, WRAP_BIND_KEY_FLAG).name] = [{
    'name': 'wrapper',
    'func': undefined
  }];

  // Add methods to `LazyWrapper`.
  LazyWrapper.prototype.clone = lazyClone;
  LazyWrapper.prototype.reverse = lazyReverse;
  LazyWrapper.prototype.value = lazyValue;

  // Add chain sequence methods to the `lodash` wrapper.
  lodash.prototype.at = wrapperAt;
  lodash.prototype.chain = wrapperChain;
  lodash.prototype.commit = wrapperCommit;
  lodash.prototype.next = wrapperNext;
  lodash.prototype.plant = wrapperPlant;
  lodash.prototype.reverse = wrapperReverse;
  lodash.prototype.toJSON = lodash.prototype.valueOf = lodash.prototype.value = wrapperValue;

  // Add lazy aliases.
  lodash.prototype.first = lodash.prototype.head;

  if (symIterator) {
    lodash.prototype[symIterator] = wrapperToIterator;
  }
  return lodash;
});

/*--------------------------------------------------------------------------*/

// Export lodash.
var _ = runInContext();

// Some AMD build optimizers, like r.js, check for condition patterns like:
if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
  // Expose Lodash on the global object to prevent errors when Lodash is
  // loaded by a script tag in the presence of an AMD loader.
  // See http://requirejs.org/docs/errors.html#mismatch for more details.
  // Use `_.noConflict` to remove Lodash from the global object.
  root._ = _;

  // Define as an anonymous module so, through path mapping, it can be
  // referenced as the "underscore" module.
  define(function() {
    return _;
  });
}
// Check for `exports` after `define` in case a build optimizer adds it.
else if (freeModule) {
  // Export for Node.js.
  (freeModule.exports = _)._ = _;
  // Export for CommonJS support.
  freeExports._ = _;
}
else {
  // Export to the global object.
  root._ = _;
}

}.call(this));