@swift-5.0.3
struct Reactive<Base> {} protocol ReactiveExtensionCompatible { associatedtype Target var rx: Reactive<Target> { get } } extension ReactiveExtensionCompatible { var rx: Reactive<Self> { fatalError() } } struct Observable<T> {} import Foundation extension NSObject: ReactiveExtensionCompatible {} // ここまでRx struct AppConfig {} protocol AppConfigProvider: NSObject { var config: AppConfig { get set } } extension AppConfigProvider { var rx: Reactive<AppConfigProvider> { fatalError() } } extension Reactive where Base == AppConfigProvider { var config: Observable<AppConfig?> { fatalError() } } func useConfig(_ provider: AppConfigProvider) { _ = provider.rx.config }
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