[Pitch] Elide `some` in Swift 6

[xwu (Xiaodi Wu)]

[Second review] SE-0390: Noncopyable structs and enums

Ah. That's good to know – thank you. If Copyable isn't viewed as an actual protocol my opinion might change here. AnyObject is a typealias to Builtin.AnyObject, but that is immaterial really—the question is what it aliases. Both AnyObject and Copyable are layout constraints, the only official ones in the language, and as the documentation for AnyObject makes clear ("The protocol to which all classes implicitly conform"), they are presented in the surface language as bona fide protocols. Sem…