public static function bound($event)
    {
        return array_key_exists($event, static::$events)
            || array_key_exists(
                $event,
                isset(static::$events['__bow.transmission.event'])
                    ? static::$events['__bow.transmission.event']
                    : []
            )
            || array_key_exists(
                $event,
                isset(static::$events['__bow.once.event']) ? static::$events['__bow.once.event'] : []
            );
    }