t-unit

let placesService = PlacesService(
    locale: .current,
    apiKey: "<key here>",
    fetcher: NetworkFetcher(session: .shared, decoder: JSONDecoder())
)

let appStore = AppStore(
    reducer: appReducer,
    state: nil,
    middleware: [

t-unit

func fetchPlaces(service: PlacesServing) -> SimpleMiddleware<AppState> {

    return { (action, context) in
        guard
            let placesAction = action as? PlacesAction,
            case .fetch = placesAction
        else {
            return action
        }

t-unit

func create(Dependency) -> Middleware

t-unit

func fetchPlaces(action: Action, context: MiddlewareContext<AppState>) -> Action? {

    // create places service
    // perform network request
    // dispatch set places action on success
}

t-unit

enum PlacesAction: Action {
    case fetch
    case set(PlacesSearchResult)
}

t-unit

func logMiddleware(action: Action, context: MiddlewareContext<AppState>) -> Action? {
    print(action)
    return action
}
let actualMiddleware = createMiddleware(logMiddleware)

t-unit

let logMiddleware: Middleware<StateType> = { dispatch, getState in
    return { next in
        return { action in
            print(action)
            next(action)
        }
    }
}

t-unit

public typealias DispatchFunction = (Action) -> Void
public typealias Middleware<State> = (@escaping DispatchFunction, @escaping () -> State?)
    -> (@escaping DispatchFunction) -> DispatchFunction

t-unit

func fetchPlaces(state: AppState, store: AppStore) -> Action? {

    let service = PlacesService([…])
    let fakeCoordinates = […]
    let radius = […]

    service.search(coordinates: fakeCoordinates, radius: radius) { result in
        guard let places = result.value else {
            return
        }

t-unit

struct FetchPlacesAction: Action { }

class ViewController: UIViewController {

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        appStore.dispatch(FetchPlacesAction())
    }
}