laravel实践21.intended方法重定向至上次请求页

public function store(Request $request)
    {
       $credentials = $this->validate($request, [
           ‘email‘ => ‘required|email|max:255‘,
           ‘password‘ => ‘required‘
       ]);

       if (Auth::attempt($credentials, $request->has(‘remember‘))) {
           session()->flash(‘success‘, ‘欢迎回来！‘);
           $fallback = route(‘users.show‘, Auth::user());
           return redirect()->intended($fallback);
       } else {
           session()->flash(‘danger‘, ‘很抱歉，您的邮箱和密码不匹配‘);
           return redirect()->back()->withInput();
       }
    }