Likely we will have to change that signature to instead of being NSSet and
Set respectively to be more compatible; however this will be an API
change. It might be good to mock up a swift translation layer for these APIs to
simulate what it would be like on Darwin if we altered these to be rename
Looking at decodeObjectOfClasses/allowedClasses – what is the element type in
the set of allowed classes? It seems like it should be AnyClass but that can’t
be added to a Set because it doesn’t implement Hashable (nor to an NSSet
because the initialiser unconditionally casts to NSObject).
— Luk
