public function tostr(...$strings)
    {
        $new_string = '';
        foreach ($strings as $temp) {
            switch (gettype($temp)) {
                case "array":
                    $it = new \RecursiveIteratorIterator(new \RecursiveArrayIterator($temp));
                    foreach($it as $v) {
                        $temp_str .= ' ' . $this->tostr($v);
                    }
                    break;
                default:
                    $temp_str = (string)$temp;
                    break;
            }
            $new_string .= $temp_str;
        }
        return trim($new_string);
    }