Question on @_objcImplementation PR

[Kyle-Ye (Kyle)]

@Jumhyn

No, this is not generally the case. Objective-C interop on Apple platforms is considered part of the public interface of the language and changes to the Objective-C interop behavior have gone through evolution review several times previously .

Speaking of it, is there any evolution proposal or doc for ObjectiveC's Protocol in Swift?

We only have a very short doc about it - Protocol | Apple Developer Documentation .And know we can pass a XXProtocol.self in Swift to make a call to an API which accepts Protocol as a parameter.

Swift metatype and ObjectiveC Protocol question

We have an ObjC API which receive a Protocol instance and return Any?. // Imported ObjectiveC API func resolve(_ p: Protocol) -> Any? // Swift Side Code @objc protocol P: NSObjectProtocol { func hello() } func test() { let p = resolve(P.self) as? P p?.hello() } In Swift side, we'd like to wrap the API to make it more swift-friendly. func resolve2<T>(_ t: T.Type) -> T? { return resolve(t) as? T // return resolve(t.self) as? T // return resolve(T.self) as? T // …