/**
  * @param $domain
  * @return string
  */
 static function textDomain($domain)
 {
     if ($domain !== NULL) {
         self::$current_domain = $domain;
         if (!isset(self::$domains[$domain])) {
             self::$domains[$domain] = array("text" => array(), "path" => array(), "load" => array(), "all_load" => false);
         }
     }
     return self::$current_domain;
 }