Ouzo\Utilities\Strings::appendPrefix PHP 메소드

    public static function appendPrefix($string, $prefix = '')
    {
        if (is_null($string)) {
            return null;
        }
        return $prefix . $string;
    }

 public static function getMessageWithHttpProtocol($code, $protocol = 'HTTP/1.1 ')
 {
     return Strings::appendPrefix(self::getMessage($code), $protocol);
 }