private function matchPair( $string, $variable )
    {
        if ( !preg_match("|" . preg_quote($this->l_delim) . 'loop ' . $variable . preg_quote($this->r_delim) . "(.+?)". preg_quote($this->l_delim) . 'end loop' . preg_quote($this->r_delim) . "|s", $string, $match ) ) {
            return false;
        }

        return $match;
    }