private static function splitParams($paramStr)
    {
        $depth = 0;
        $startPos = 0;
        $chars = \str_split($paramStr);
        $params = array();
        foreach ($chars as $pos => $char) {
            switch ($char) {
                case ',':
                    if ($depth === 0) {
                        $params[] = \trim(\substr($paramStr, $startPos, $pos-$startPos));
                        $startPos = $pos + 1;
                    }
                    break;
                case '[':
                case '(':
                    $depth ++;
                    break;
                case ']':
                case ')':
                    $depth --;
                    break;
            }
        }
        $params[] = \trim(\substr($paramStr, $startPos, $pos+1-$startPos));
        return $params;
    }