Leafo\ScssPhp\Parser::argumentList PHP Method

    protected function argumentList(&$out)
    {
        $s = $this->seek();
        $this->literal('(');
        $args = [];
        while ($this->keyword($var)) {
            if ($this->literal('=') && $this->expression($exp)) {
                $args[] = [Type::T_STRING, '', [$var . '=']];
                $arg = $exp;
            } else {
                break;
            }
            $args[] = $arg;
            if (!$this->literal(',')) {
                break;
            }
            $args[] = [Type::T_STRING, '', [', ']];
        }
        if (!$this->literal(')') || !count($args)) {
            $this->seek($s);
            return false;
        }
        $out = $args;
        return true;
    }