さっきの #combine で話してた
Future の get 、 Failure が Never のときだけ Result<Output, Never> じゃなくて Output で受け取るようにできた。 @available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *) extension Future { @_disfavoredOverload public func get(_ body: @escaping (Result<Output, Failure>) -> Void) { let keep: Keep<AnyCancellable> = .init() keep.value = sink(receiveCompletion: { completion in switch completion { case .finished: break case .failure(let error): body(.failure(error)) } keep.value = nil }, receiveValue: { output in body(.success(output)) }) } } @available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *) extension Future where Failure == Never { public func get(_ body: @escaping (Output) -> Void) { let keep: Keep<AnyCancellable> = .init() keep.value = sink { output in body(output) keep.value = nil } } } private class Keep<Value> { var value: Value? }