Parkour\Traverse::customFilter PHP Method

    public static function customFilter(array $data, callable $cb, $keyed = true)
    {
        $filtered = [];
        foreach ($data as $key => $value) {
            if (call_user_func($cb, $value, $key)) {
                if ($keyed) {
                    $filtered[$key] = $value;
                } else {
                    $filtered[] = $value;
                }
            }
        }
        return $filtered;
    }