Please allow non-public members to implicitly implement non-public interfaces

[alrz]

internal interface I
{
  void M();
}

public class C : I
{
  protected internal virtual void M() {}
}

In other words, M must not be less accessible than I rather than required to be public.

Currently the workaround is to explicitly implement I to delegate corresponding non-public members.

Q: Should the accessibility of C also be taken into account?

[bondsbw]

Related: #3599

[alrz]

@bondsbw

"Allow implicit implementation of internal interfaces" This is currently possible and the example suggests to add internal modifier on interface members which doesn't add up. I think that's a little misleading.

[bondsbw]

Agreed, the issue name is misleading.

But unless I'm misunderstanding one of the proposals, they are substantially the same. Though I believe yours goes a bit further in allowing protected internal instead of just internal.

[alrz]

@gafter I'd appreciate it if you could clarify if there is anything wrong with the suggestion. Thanks!

[gafter]

@alrz I don't think this would be a bad idea necessarily, but it has marginal value compared to many other things we could do. If you think of any proposal as starting with -100 or -1000 points, it is hard to see how the value added rises above that.