code: protected function canSkipRule($ruleToCall, $value)
      {
          return (
              (is_array($ruleToCall) &&
              method_exists($ruleToCall[0], 'canSkip') &&
              $ruleToCall[0]->canSkip()) ||
              empty($value) &&
              !is_array($value)
          );
      }
docs: Method to help skip a rule if a value is empty, since we
  don't need to validate an empty value. If the rule to
  call specifically doesn't allowing skipping, then
  we don't want skip the rule.
  
  @param  array $ruleToCall
  @param  mixed $value
  
  @return null