code: function() {
              var args;
              if (arguments.length === 0) {
                  args = undefined;
              } else if (arguments.length === 1) {
                  args = arguments[0];
              }
  
              return {
                  getInitialState: function() {
                      return xhrFactory.getInitialState(args, this);
                  },
  
                  componentDidMount: function() {
                      return xhrFactory.componentDidMount(args, this);
                  }
              };
          }
docs: If the model executes *any* XHR activity, the internal state "loading" attribute
  will be set to true and, if an error occurs with loading, the "error" state attribute
  will be set with the error contents