class Hash

Public Instance Methods

assert_valid_keys(*valid_keys) click to toggle source

Validates all keys in a hash match *valid_keys, raising ArgumentError on a mismatch.

Note that keys are treated differently than HashWithIndifferentAccess, meaning that string and symbol keys will not match.

{ name: 'Rob', years: '28' }.assert_valid_keys(:name, :age) # => raises "ArgumentError: Unknown key: :years. Valid keys are: :name, :age"
{ name: 'Rob', age: '28' }.assert_valid_keys('name', 'age') # => raises "ArgumentError: Unknown key: :name. Valid keys are: 'name', 'age'"
{ name: 'Rob', age: '28' }.assert_valid_keys(:name, :age)   # => passes, raises nothing
# File lib/flow/cli/vendors/hash.rb, line 142
def assert_valid_keys(*valid_keys)
  valid_keys.flatten!
  each_key do |k|
    unless valid_keys.include?(k)
      raise ArgumentError, "Unknown key: #{k.inspect}. Valid keys are: #{valid_keys.map(&:inspect).join(', ')}"
    end
  end
end
compact() click to toggle source
# File lib/flow/cli/vendors/hash.rb, line 49
def compact
  reject { |_, value| value.nil? }
end
compact!() click to toggle source
# File lib/flow/cli/vendors/hash.rb, line 53
def compact!
  reject! { |_, value| value.nil? }
end
deep_stringify_keys() click to toggle source

Returns a new hash with all keys converted to strings. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { person: { name: 'Rob', age: '28' } }

hash.deep_stringify_keys
# => {"person"=>{"name"=>"Rob", "age"=>"28"}}
# File lib/flow/cli/vendors/hash.rb, line 178
def deep_stringify_keys
  deep_transform_keys(&:to_s)
end
deep_stringify_keys!() click to toggle source

Destructively converts all keys to strings. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/flow/cli/vendors/hash.rb, line 185
def deep_stringify_keys!
  deep_transform_keys!(&:to_s)
end
deep_symbolize_keys() click to toggle source

Returns a new hash with all keys converted to symbols, as long as they respond to to_sym. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { 'person' => { 'name' => 'Rob', 'age' => '28' } }

hash.deep_symbolize_keys
# => {:person=>{:name=>"Rob", :age=>"28"}}
# File lib/flow/cli/vendors/hash.rb, line 197
def deep_symbolize_keys
  deep_transform_keys do |key|
    begin
                                key.to_sym
                              rescue
                                key
                              end
  end
end
deep_symbolize_keys!() click to toggle source

Destructively converts all keys to symbols, as long as they respond to to_sym. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/flow/cli/vendors/hash.rb, line 210
def deep_symbolize_keys!
  deep_transform_keys! do |key|
    begin
                                 key.to_sym
                               rescue
                                 key
                               end
  end
end
deep_transform_keys(&block) click to toggle source

Returns a new hash with all keys converted by the block operation. This includes the keys from the root hash and from all nested hashes and arrays.

hash = { person: { name: 'Rob', age: '28' } }

hash.deep_transform_keys{ |key| key.to_s.upcase }
# => {"PERSON"=>{"NAME"=>"Rob", "AGE"=>"28"}}
# File lib/flow/cli/vendors/hash.rb, line 159
def deep_transform_keys(&block)
  _deep_transform_keys_in_object(self, &block)
end
deep_transform_keys!(&block) click to toggle source

Destructively converts all keys by using the block operation. This includes the keys from the root hash and from all nested hashes and arrays.

# File lib/flow/cli/vendors/hash.rb, line 166
def deep_transform_keys!(&block)
  _deep_transform_keys_in_object!(self, &block)
end
extract!(*keys) click to toggle source

Removes and returns the key/value pairs matching the given keys.

{ a: 1, b: 2, c: 3, d: 4 }.extract!(:a, :b) # => {:a=>1, :b=>2}
{ a: 1, b: 2 }.extract!(:a, :x)             # => {:a=>1}
# File lib/flow/cli/vendors/hash.rb, line 45
def extract!(*keys)
  keys.each_with_object(self.class.new) { |key, result| result[key] = delete(key) if key?(key) }
end
slice(*keys) click to toggle source

Slice a hash to include only the given keys. Returns a hash containing the given keys.

{ a: 1, b: 2, c: 3, d: 4 }.slice(:a, :b)
# => {:a=>1, :b=>2}

This is useful for limiting an options hash to valid keys before passing to a method:

def search(criteria = {})
  criteria.assert_valid_keys(:mass, :velocity, :time)
end

search(options.slice(:mass, :velocity, :time))

If you have an array of keys you want to limit to, you should splat them:

valid_keys = [:mass, :velocity, :time]
search(options.slice(*valid_keys))
# File lib/flow/cli/vendors/hash.rb, line 21
def slice(*keys)
  keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true)
  keys.each_with_object(self.class.new) { |k, hash| hash[k] = self[k] if key?(k) }
end
slice!(*keys) click to toggle source

Replaces the hash with only the given keys. Returns a hash containing the removed key/value pairs.

{ a: 1, b: 2, c: 3, d: 4 }.slice!(:a, :b)
# => {:c=>3, :d=>4}
# File lib/flow/cli/vendors/hash.rb, line 31
def slice!(*keys)
  keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true)
  omit = slice(*self.keys - keys)
  hash = slice(*keys)
  hash.default      = default
  hash.default_proc = default_proc if default_proc
  replace(hash)
  omit
end
stringify_keys() click to toggle source

Returns a new hash with all keys converted to strings.

hash = { name: 'Rob', age: '28' }

hash.stringify_keys
# => {"name"=>"Rob", "age"=>"28"}
# File lib/flow/cli/vendors/hash.rb, line 92
def stringify_keys
  transform_keys(&:to_s)
end
stringify_keys!() click to toggle source

Destructively converts all keys to strings. Same as stringify_keys, but modifies self.

# File lib/flow/cli/vendors/hash.rb, line 98
def stringify_keys!
  transform_keys!(&:to_s)
end
symbolize_keys() click to toggle source

Returns a new hash with all keys converted to symbols, as long as they respond to to_sym.

hash = { 'name' => 'Rob', 'age' => '28' }

hash.symbolize_keys
# => {:name=>"Rob", :age=>"28"}
# File lib/flow/cli/vendors/hash.rb, line 109
def symbolize_keys
  transform_keys do |key|
    begin
                           key.to_sym
                         rescue
                           key
                         end
  end
end
Also aliased as: to_options
symbolize_keys!() click to toggle source

Destructively converts all keys to symbols, as long as they respond to to_sym. Same as symbolize_keys, but modifies self.

# File lib/flow/cli/vendors/hash.rb, line 122
def symbolize_keys!
  transform_keys! do |key|
    begin
                            key.to_sym
                          rescue
                            key
                          end
  end
end
Also aliased as: to_options!
to_options()
Alias for: symbolize_keys
to_options!()
Alias for: symbolize_keys!
transform_keys() { |key| ... } click to toggle source

Returns a new hash with all keys converted using the block operation.

hash = { name: 'Rob', age: '28' }

hash.transform_keys { |key| key.to_s.upcase } # => {"NAME"=>"Rob", "AGE"=>"28"}

If you do not provide a block, it will return an Enumerator for chaining with other methods:

hash.transform_keys.with_index { |k, i| [k, i].join } # => {"name0"=>"Rob", "age1"=>"28"}
# File lib/flow/cli/vendors/hash.rb, line 67
def transform_keys
  return enum_for(:transform_keys) { size } unless block_given?
  result = {}
  each_key do |key|
    result[yield(key)] = self[key]
  end
  result
end
transform_keys!() { |key| ... } click to toggle source

Destructively converts all keys using the block operations. Same as transform_keys but modifies self.

# File lib/flow/cli/vendors/hash.rb, line 78
def transform_keys!
  return enum_for(:transform_keys!) { size } unless block_given?
  keys.each do |key|
    self[yield(key)] = delete(key)
  end
  self
end

Private Instance Methods

_deep_transform_keys_in_object(object) { |key| ... } click to toggle source

support methods for deep transforming nested hashes and arrays

# File lib/flow/cli/vendors/hash.rb, line 223
def _deep_transform_keys_in_object(object, &block)
  case object
  when Hash
    object.each_with_object({}) do |(key, value), result|
      result[yield(key)] = _deep_transform_keys_in_object(value, &block)
    end
  when Array
    object.map { |e| _deep_transform_keys_in_object(e, &block) }
  else
    object
  end
end
_deep_transform_keys_in_object!(object) { |key| ... } click to toggle source
# File lib/flow/cli/vendors/hash.rb, line 236
def _deep_transform_keys_in_object!(object, &block)
  case object
  when Hash
    object.keys.each do |key|
      value = object.delete(key)
      object[yield(key)] = _deep_transform_keys_in_object!(value, &block)
    end
    object
  when Array
    object.map! { |e| _deep_transform_keys_in_object!(e, &block) }
  else
    object
  end
end