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::$events['__bow.once.event'] : []
            );
    }
public static function bound($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'] : []
            );
    }
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' ] : [ ] ) ; }
Check whether an event is already recorded at least once.

@param  string $event
@return bool
Check whether an event is already recorded at least once .