using declaration on any block

[maxtoroq]

Example:

class MyClass {
   using Foo;

   void MyMethod() {
      using Bar;

      // Foo and Bar visible

      using Baz;

      // Foo, Bar and Baz visible
   }
}

[DavidArno]

What would using Foo; actually end up as in any expanded, compile-time, code? Presumably using Foo is just shorthand for eg

private readonly using Foo SomeFoo = new Foo();

and thus you'd presumably want Myclass.Finalize() to be auto-implemented/extended at compile time to ensure ((IDisposable)Foo).Dispose(); was called when the MyClass instance was garbage collected?

[HaloFour]

@maxtoroq What exactly are Foo, Bar or Baz? How does this translate to existing code? It's difficult to tell because you provide very little context and your code sample seems very incomplete, but if I had to guess I would say that it's a dupe of dotnet/roslyn#181.

[alrz]

I think this ain't about disposables. It's more likely to be a duplicate of dotnet/roslyn#4491.

[HaloFour]

Ah, makes sense. Context is useful.

[alrz]

Using this you can make yourself a scoped Self type (if you have multiple types in a file),

class C
{
  using Self = C;
}

You can use an analyzer to make sure that type aliases named Self are identical to the enclosing type.

[Thaina]

I think this would also enable my proposal

dotnet/roslyn#16958