protected function notifyLoadRoute(IRequest $request)
 {
     $event = new Event($this, 'route.load', array('request' => $request));
     $this->emitter->notifyUntil($event);
     if (!$event->isHandled()) {
         throw new NotFoundHttpException("No route found for '{$request->getPathInfo()}' request");
     }
     return $event->getValue();
 }