code: function makeError(jqXHR, textStatus, errorThrown, options) {
      var Constructor = statusToError[textStatus];
  
      // We did not find anything in the map, which would happen if the textStatus
      // was "error". Determine whether an ``HttpError`` or an ``AjaxError`` must
      // be thrown.
      if (!Constructor) {
        Constructor = statusToError[(jqXHR.status !== 0) ? "http" : "ajax"];
      }
  
      return new Constructor(jqXHR, textStatus, errorThrown, options);
    }
docs: Given a ``jqXHR`` that failed, create an error object.