public static function insertAfter(array &$arr, $key, array $inserted): void
    {
        $offset = self::searchKey($arr, $key);
        if ($offset === null) {
            $arr += $inserted;
        } else {
            ++$offset;
            $arr = \array_slice($arr, 0, $offset, true) + $inserted + \array_slice($arr, $offset, null, true);
        }
    }