pocketmine\event\HandlerList::register PHP Méthode

    public function register(RegisteredListener $listener)
    {
        if ($listener->getPriority() < EventPriority::MONITOR or $listener->getPriority() > EventPriority::LOWEST) {
            return;
        }
        if (isset($this->handlerSlots[$listener->getPriority()][spl_object_hash($listener)])) {
            throw new \InvalidStateException("This listener is already registered to priority " . $listener->getPriority());
        }
        $this->handlers = null;
        $this->handlerSlots[$listener->getPriority()][spl_object_hash($listener)] = $listener;
    }