public function __invoke(ElementInterface $element = null)
 {
     if ($element && !$element->hasAttribute('class')) {
         $this->addClass($element, 'form-control');
     }
     return parent::__invoke($element);
 }
 /**
  * Password
  *
  * @param ElementInterface|null $element
  * @return string|Helper\FormInput
  */
 public function password(ElementInterface $element = null)
 {
     $helper = new Helper\FormPassword();
     return $helper->__invoke($element);
 }