docs: function (cb, scope) {
              var es = this.__entrySet(), ret = new this._static();
              es = es.filter.apply(es, arguments);
              for (var i = es.length - 1; i >= 0; i--) {
                  var e = es[i];
                  ret.put(e.key, e.value);
              }
              return ret;
          }