public function hasDocTypes() {
    $doc_comment = $this->getFunction()->getDocComment();
    if (!$doc_comment) {
      return FALSE;
    }
    $param_tag = $doc_comment->getParameter($this->getName());
    if (!$param_tag) {
      return FALSE;
    }
    $types = $param_tag->getTypes();
    return !empty($types);
  }