Using with enum class (C++20)

1. Przykład 1

 enum class Status { Unknown, Created, Connected };
 void process(Status const s)
 {
   switch (s)
   {
     using enum Status;
     case Unknown:   /*...*/ break;
     case Created:   /*...*/ break;
     case Connected: /*...*/ break;
   }
 }

1. Przykład 2

   struct foo
   {
     enum class Status { Unknown, Created, Connected };
     using enum Status;
   };
   foo::Status s = foo::Created; // instead of
                               // foo::Status::Created