public function quote($string)
    {
        if ($quoter = $this->quoter()) {
            return $quoter($string);
        }
        $replacements = array(
            "\x00"=>'\x00',
            "\n"=>'\n',
            "\r"=>'\r',
            "\\"=>'\\\\',
            "'"=>"\'",
            "\x1a"=>'\x1a'
        );
        return "'" . strtr(addcslashes($string, '%_'), $replacements) . "'";
    }