atimca

func transform(newsReducer: (NewsState, NewsEvent) -> NewsState) -> Reducer

atimca

func transform(
    newsReducer: @escaping (NewsState, NewsEvent) -> NewsState,
    stateKeyPath: WritableKeyPath<AppState, NewsState>
) -> Reducer {
    return { appState, appEvent in
        var appState = appState
        appState[keyPath: stateKeyPath] = newsReducer(appState[keyPath: stateKeyPath], appEvent)
        return appState
    }
}

atimca

enum AppEvent {
    case newUserWasLoaded(User)
    case newsEvents(NewsEvent)
    var newsEvent: NewsEvent? {
        guard case .newsEvents(let event) = self else { return nil }
        return event
    }
}

atimca

func transform(
    newsReducer: @escaping (NewsState, NewsEvent) -> NewsState,
    stateKeyPath: WritableKeyPath<AppState, NewsState>
) -> Reducer {
    return { appState, appEvent in
        guard let newsEvent = appEvent.newsEvent else { return appState }
        var appState = appState
        appState[keyPath: stateKeyPath] = newsReducer(appState[keyPath: stateKeyPath], newsEvent)
        return appState
    }

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func transform(
    newsReducer: @escaping (NewsState, NewsEvent) -> NewsState,
    stateKeyPath: WritableKeyPath<AppState, NewsState>,
    toNewsEvent: @escaping (AppEvent) -> NewsEvent?
) -> Reducer {
    return { appState, appEvent in
        guard let newsEvent = toNewsEvent(appEvent) else { return appState }
        var appState = appState
        appState[keyPath: stateKeyPath] = newsReducer(appState[keyPath: stateKeyPath], newsEvent)
        return appState

atimca

func combine<State, Event>(_ reducers: (State, Event) -> State...) -> (State, Event) -> State {
    return { state, event in
        reducers.reduce(state) { state, reducer in
            reducer(state, event)
        }
    }
}
func transform<GlobalState, GlobalEvent, LocalState, LocalEvent>(
    localReducer: @escaping (LocalState, LocalEvent) -> LocalState,
    stateKeyPath: WritableKeyPath<GlobalState, LocalState?>,

atimca

let appReducer: Reducer = { state, event in
    var state = state
    switch event {
    case .newUserWasLoaded(let user):
        state.user = user
    default:
        return state
    }
    return state
}

atimca

class NewsStore {
    @Published private(set) var state: NewsState
    private let reducer: (NewsState, NewsEvent) -> NewsState
    init(
        initialState: NewsState,
        reducer: @escaping (NewsState, NewsEvent) -> NewsState
    ) {
        self.state = initialState
        self.reducer = reducer
    }

atimca

class ViewController: UIViewController {
    var cancellables: Set<AnyCancellable> = []
}
enum InputEvent {
    case newUserWasLoaded(User)
    var user: User {
        switch self {
        case .newUserWasLoaded(let user):
            return user
        }

atimca

class ViewController: UIViewController {
    var cancellables: Set<AnyCancellable> = []
}
enum InputEvent {
    case newUserWasLoaded(User)
    var user: User {
        switch self {
        case .newUserWasLoaded(let user):
            return user
        }