code: function () {
        var path = Immutable.List();
        for (var i = 0; i < arguments.length - 1; i++) {
          path = path.concat(arguments[i]);
        }
        var value = arguments[arguments.length - 1];
        this.state = this.state.setIn(path, value);
        this.emitChange();
      }
docs: .setState(path Array, value Object) :void