public function get_page_type_strings($type=null, $special=true) {
        $types = array();
        foreach ($this->types as $pagetype) {
            if (($type===null || $pagetype->type===$type) && ($special===true || $pagetype->is_standard())) {
                $types[$pagetype->typeid] = $pagetype->typestring;
            }
        }
        return $types;
    }