public static function export(array $arr): string
    {
        $str = var_export($arr, true);
        $str = str_replace("array (", "array(", $str);
        $str = preg_replace("/=>(\s+)array\(/s", "=> array(", $str);
        $str = preg_replace("/array\(\s+\)/", "array()", $str);
        return $str;
    }