[swift-evolution] [Pitch] merge types and protocols back together with type<Type, Protocol, ...>

[Tino Heth]

> func f(obj: A&B&C) {..}
> if obj is A&B&C {...}
> obj2 = obj as! A&B&C
> 
> (but I still don't understand real use case of things like (String | Int))
Ceylon has already been mentioned: It uses the concept for its optionals.
Swift uses enums, and those could be made obsolete by union types.