protected static function unescapeString($matches) {
		static $map = ['n' => "\n", 'r' => "\r", 't' => "\t", 'v' => "\v", 'f' => "\f"];
		
		if (!empty($matches[2]))
			return chr(octdec($matches[2]));
		elseif (!empty($matches[3]))
			return chr(hexdec($matches[3]));
		elseif (isset($map[$matches[1]]))
			return $map[$matches[1]];
		
		return $matches[1];
	}