public function getNFirst($n)
    {
        $it = new \ArrayIterator();
        $j = 0;
        foreach ($this as $file) {
            if ($j == $n) {
                break;
            }
            $j++;
            $it->append($file);
        }

        $finder = new static();
        $finder->append($it);

        return $finder;
    }