protected function instance($class)
    {
        $reflection = new \ReflectionClass($class);

        $arguments = array();

        $constructor = $reflection->getConstructor();

        if ($this->container->has($class))
        {
            return $this->container->get($class);
        }

        if ($constructor !== null)
        {
            $arguments = $this->arguments($constructor);
        }

        return $reflection->newInstanceArgs($arguments);
    }