code: function(element) {
      if('TEXTAREA'===element.nodeName || 'SELECT'===element.nodeName
        || ('INPUT'===element.nodeName&&element.hasAttribute('type')
          &&('text'===element.getAttribute('type')
            || 'number'===element.getAttribute('type')
            || 'password'===element.getAttribute('type')
            || 'file'===element.getAttribute('type')
            || 'date'===element.getAttribute('type'))
        )
      ) {
        return true;
      }
      return false;
    }
docs: Tell if the element is a form element that can contain a value