Auth 类没有引入，为什么能在_hearder 视图里面用 Auth::check () 方法?

在IDE里看起来是没有引入包，但实际上肯定是导入了，只是IDE不太牛逼而已，

Facades 和 Class Aliases:

'Auth' => Illuminate\Support\Facades\Auth::class,

In the config/app.php

In the vendor/laravel/framework/src/Illuminate/Support/Facades/Auth.php

There is no check() method declared explictly, but because the Auth class extents Facade class.

In the vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php

There is also no check() method declared explictly, but a magic method is quietly hiding in the bottom.

So in fact, auth::check() is equal to SessionGuard::check() which is the Root object behind the facde.

FYA: the SessionGuard class use the trait GuardHelpers which contains the check() method explictly!