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);

    },



    electricChars: outer.electricChars,



    innerMode: function(state) {

      return state.inner ? {state: state.inner, mode: state.innerActive.mode} : {state: state.outer, mode: outer};

    }

  };

};

