public function url()
    {
        if (empty($parameters = func_get_args())) {
            return $this->to('/');
        }

        $path = array_shift($parameters);

        $result = preg_replace_callback('#\{(\d+)\}#', function ($matches) use ($parameters)
        {
            list ($value, $key) = $matches;

            return isset($parameters[$key]) ? $parameters[$key] : $value;

        }, $path);

        return $this->to($path);
    }