GraphQL\Utils::chr PHP Метод

    public static function chr($ord, $encoding = 'UTF-8')
    {
        if ($ord <= 255) {
            return chr($ord);
        }
        if ($encoding === 'UCS-4BE') {
            return pack("N", $ord);
        } else {
            return mb_convert_encoding(self::chr($ord, 'UCS-4BE'), $encoding, 'UCS-4BE');
        }
    }

 /**
  * @param $code
  * @return string
  */
 public static function printCharCode($code)
 {
     if (null === $code) {
         return '<EOF>';
     }
     return $code < 0x7f ? json_encode(Utils::chr($code)) : '"\\u' . dechex($code) . '"';
 }