/**
  * Register a class loader as a delegate
  *
  * @param   lang.IClassLoader l
  * @param   bool before default FALSE whether to register this as the first loader
  * @return  lang.IClassLoader the registered loader
  */
 public static function registerLoader(IClassLoader $l, $before = FALSE)
 {
     if ($before) {
         self::$delegates = array_merge(array($l->instanceId() => $l), self::$delegates);
     } else {
         self::$delegates[$l->instanceId()] = $l;
     }
     return $l;
 }