↓おもしろ。 @swiftbot

extension Never: Equatable { public static func == (lhs: Never, rhs: Never) -> Bool { switch (lhs, rhs) { } } } let a: [Never] = [] print(a == a) // OK

https://github.com/apple/swift-evolution/blob/master/proposals/0215-conform-never-to-hashable-and-equatable.md (edited)

apple/swift-evolution

swift-evolution - This maintains proposals for changes and user-visible enhancements to the Swift Programming Language.