atimca

enum State {
    case initial
    case loading
    case loaded(data: [String])
}
enum Event {
    case dataLoaded(data: [String])
    case loadData
}
extension State {

atimca

public func scope<LocalState, LocalEvent: ComponentableEvent>(
    state toLocalState: @escaping (State) -> LocalState,
    event toGlobalEvent: @escaping (LocalEvent) -> Event,
    feedBacks: [SideEffect<LocalState, LocalEvent>]
) -> Store<LocalState, LocalEvent> where LocalEvent.State == LocalState {
    let localStore = Store<LocalState, LocalEvent>(
        initial: toLocalState(state),
        feedBacks: feedBacks,
        reducer: { localState, localEvent in
            var state = self.state

atimca

public func scope<LocalState, LocalEvent: ComponentableEvent>(
    state toLocalState: @escaping (State) -> LocalState,
    event toGlobalEvent: @escaping (LocalEvent) -> Event,
    feedBacks: [SideEffect<LocalState, LocalEvent>]
) -> Store<LocalState, LocalEvent> where LocalEvent.State == LocalState {
    let localStore = Store<LocalState, LocalEvent>(
        initial: toLocalState(state),
        feedBacks: feedBacks,
        reducer: { localState, localEvent in
            var state = self.state

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
        }

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

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

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

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 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
    }