docs: function (promise, i) {
              var self = this;
              promise.then(
                  function () {
                      var args = argsToArray(arguments);
                      args.unshift(i);
                      spreadArgs(self.callback, args, self);
                      promise = i = self = null;
                  },
                  function () {
                      var args = argsToArray(arguments);
                      args.unshift(i);
                      spreadArgs(self.errback, args, self);
                      promise = i = self = null;
                  });
          }