> I'd like to see a feature-test for LWG2296, "std::addressof should
> be
> constexpr"
> (http://wiki.edg.com/pub/Wg21jacksonville/StrawPolls/P0304R0.html).

Would it not be possible to test for that using SFINAE, or some other
template trick?

> For P0036, "Unary Folds and Empty Parameter Packs", maybe bump
> `__cpp_fold_expressions`?

That's a thought.

But if there is really code out there that wants to use the deleted
identities when they are available, then didn't the committee make a
mistake in getting rid of them? (Especially without deprecating them
first.)

Clark