src/Utils.php
public static function unicodeChr($code) {
        // TODO this works by order of magnitude slower then chr()
        $code = sprintf("%04x", $code);
        $char = json_decode('"\u'.$code.'"');
        $char = iconv('UTF-8', mb_internal_encoding(), $char);

        return $char;
    }
public static function unicodeChr($code) {
        // TODO this works by order of magnitude slower then chr()
        $code = sprintf("%04x", $code);
        $char = json_decode('"\u'.$code.'"');
        $char = iconv('UTF-8', mb_internal_encoding(), $char);

        return $char;
    }
Multibyte replacement for standard chr()

@param int $code Character code.

@return string Char with given code