public function strings_for_js($identifiers, $component, $a = null) {
        foreach ($identifiers as $key => $identifier) {
            if (is_array($a) && array_key_exists($key, $a)) {
                $extra = $a[$key];
            } else {
                $extra = $a;
            }
            $this->string_for_js($identifier, $component, $extra);
        }
    }