CSSmin::replace_string PHP Method

    private function replace_string($matches)
    {
        $match = $matches[0];
        $quote = substr($match, 0, 1);
        // Must use addcslashes in PHP to avoid parsing of backslashes
        $match = addcslashes($this->str_slice($match, 1, -1), '\\');
        // maybe the string contains a comment-like substring?
        // one, maybe more? put'em back then
        if (($pos = $this->index_of($match, self::COMMENT)) >= 0) {
            for ($i = 0, $max = count($this->comments); $i < $max; $i++) {
                $match = preg_replace('/' . self::COMMENT . $i . '___/', $this->comments[$i], $match, 1);
            }
        }
        // minify alpha opacity in filter strings
        $match = preg_replace('/progid\\:DXImageTransform\\.Microsoft\\.Alpha\\(Opacity\\=/i', 'alpha(opacity=', $match);
        $this->preserved_tokens[] = $match;
        return $quote . self::TOKEN . (count($this->preserved_tokens) - 1) . '___' . $quote;
    }