public function invokeCallbacks($event, $arg)
    {
        $this->checkEventType($event);
        foreach ($this->events[$event] as $callback) {
            call_user_func($callback, $arg);
        }
    }
public function invokeCallbacks($event, $arg)
    {
        $this->checkEventType($event);
        foreach ($this->events[$event] as $callback) {
            call_user_func($callback, $arg);
        }
    }
public function invokeCallbacks ( $ event , $ arg ) { $ this -> checkEventType ( $ event ) ; foreach ( $ this -> events [ $ event ] as $ callback ) { call_user_func ( $ callback , $ arg ) ; } }
Invokes callbacks registered for given event

@param string $event
@param mixed $arg
@throws InvalidArgumentException
Invokes callbacks registered for given event