未找到类Die和Dump环境变量键

I am going through a laravel tutorial and the section I am stuck on is called "The Service Container" Basically I just grab a environment variable and spit it out to the page with a dd() die and dump. However I get a class not found error. I know it must be a small bug, but cant quite figure it out. I tried running composer dump-autoload with no luck.

Here is my code

routes/web.php

App::bind('App\Billing\Stripe', function(){

    return new \App\Billing\Stripe(config('services.stripe.secret'));

});

$stripe = App::make('App\Billing\Stripe');

dd($stripe);

app/billing/Stripe.php

namespace App\Billing;

class Stripe{

  protected $key;

  public function __construct($key){

    $this->key = $key;

  }

}

There is no need here for dump-autoload because you're creating a new namespace inside psr-4 confiugred folder app.

The solution is to rename the folder billing to a capital case, because laravel uses composer autoload following psr-4 standard which states that namespace matches the folder name in a case sensitive way.

Note : there are alternative autoloading schemes provided by composer that may need composer dump-autoload or editing composer.json when a new file is created