docs: function (value, resolvedCallback, rejectCallback, progressCallback) {
              if (this.isPromise(value)) {
                  return value.then(resolvedCallback, rejectCallback, progressCallback);
              }
              var deferred = this.defer();
              deferred.then(resolvedCallback, rejectCallback, progressCallback);
              deferred.emitSuccess(value);
  
              return deferred.getPromise();
          }