docs: function (propType) {
          return {
              propType: propType,
              update: function domAttribute_update(winjsComponent, propName, oldValue, newValue) {
                  if (oldValue !== newValue) {
                      if (newValue !== null && newValue !== undefined) {
                          winjsComponent.element.setAttribute(propName, "" + newValue);
                      } else {
                          winjsComponent.element.removeAttribute(propName);
                      }
                  }
              }
          };
      }