CodeMirror.multiplexingMode = function(outer /*, others */) {

// Others should be {open, close, mode [, delimStyle]} objects
var others = Array.prototype.slice.call(arguments, 1);
var n_others = others.length;

function indexOf(string, pattern, from) {
  if (typeof pattern == "string") return string.indexOf(pattern, from);
  var m = pattern.exec(from ? string.slice(from) : string);
  return m ? m.index + from : -1;
}

return {
  startState: function() {
    return {
      outer: CodeMirror.startState(outer),
      innerActive: null,
      inner: null
    };
  },

  copyState: function(state) {
    return {
      outer: CodeMirror.copyState(outer, state.outer),
      innerActive: state.innerActive,
      inner: state.innerActive && CodeMirror.copyState(state.innerActive.mode, state.inner)
    };
  },

  token: function(stream, state) {
    if (!state.innerActive) {
      var cutOff = Infinity, oldContent = stream.string;
      for (var i = 0; i < n_others; ++i) {
        var other = others[i];
        var found = indexOf(oldContent, other.open, stream.pos);
        if (found == stream.pos) {
          stream.match(other.open);
          state.innerActive = other;
          state.inner = CodeMirror.startState(other.mode, outer.indent ? outer.indent(state.outer, "") : 0);
          return other.delimStyle;
        } else if (found != -1 && found < cutOff) {
          cutOff = found;
        }
      }
      if (cutOff != Infinity) stream.string = oldContent.slice(0, cutOff);
      var outerToken = outer.token(stream, state.outer);
      if (cutOff != Infinity) stream.string = oldContent;
      return outerToken;
    } else {
      var curInner = state.innerActive, oldContent = stream.string;
      var found = indexOf(oldContent, curInner.close, stream.pos);
      if (found == stream.pos) {
        stream.match(curInner.close);
        state.innerActive = state.inner = null;
        return curInner.delimStyle;
      }
      if (found > -1) stream.string = oldContent.slice(0, found);
      var innerToken = curInner.mode.token(stream, state.inner);
      if (found > -1) stream.string = oldContent;
      var cur = stream.current(), found = cur.indexOf(curInner.close);
      if (found > -1) stream.backUp(cur.length - found);
      return innerToken;
    }
  },

  indent: function(state, textAfter) {
    var mode = state.innerActive ? state.innerActive.mode : outer;
    if (!mode.indent) return CodeMirror.Pass;
    return mode.indent(state.innerActive ? state.inner : state.outer, textAfter);
  },

  blankLine: function(state) {
    var mode = state.innerActive ? state.innerActive.mode : outer;
    if (mode.blankLine) {
      mode.blankLine(state.innerActive ? state.inner : state.outer);
    }
    if (!state.innerActive) {
      for (var i = 0; i < n_others; ++i) {
        var other = others[i];
        if (other.open === "\n") {
          state.innerActive = other;
          state.inner = CodeMirror.startState(other.mode, mode.indent ? mode.indent(state.outer, "") : 0);
        }
      }
    } else if (mode.close === "\n") {
      state.innerActive = state.inner = null;
    }
  },

  electricChars: outer.electricChars,

  innerMode: function(state) {
    return state.inner ? {state: state.inner, mode: state.innerActive.mode} : {state: state.outer, mode: outer};
  }
};

};