djds23

extension SKAction {
    static func write<Root: AnyObject, Value>(
        value: Value,
        to keyPath: ReferenceWritableKeyPath<Root, Value>,
        on object: Root
    ) -> SKAction {
        SKAction.customAction(withDuration: 0) { [weak object] _, _ in
            object?[keyPath: keyPath] = value
        }

djds23

/*

The answers to each of these questions should be written as a function.

Call the function to execute your code.

Open this file in a text editor like "Sublime Text" or "Notepad++"

Write your answers in this file, saving often. 

djds23

/*

The answers to each of these questions should be written as a function.

Call the function to execute your code.

Open this file in a text editor like "Sublime Text" or "Notepad++"

Write your answers in this file, saving often. 

djds23

let output = "";
let character = "#";
for (let count = 0; count < 7; count += 1) {
  output += character;
  console.log(output);
}

djds23

import Foundation

enum MovieGenre: Int, Codable {
	case action, horror, art, comedy, drama
}

let genre: MovieGenre = .action
let encoder = JSONEncoder()
// On the follow line, the code raises Swift.EncodingError.invalidValue
let jsonValue = try! encoder.encode(genre) 

djds23

class TrainDepartureService {

  func departureTimes(forLine: TrainLine, departingFrom: TrainStation) -> Observable<Date> {
    return Observable<TimeInterval>.timer(0, period: 60, scheduler: scheduler)
      .flatMapLatest { _ -> Observable<Date> in
        network.departureTime(forLine: forLine, departingFrom: departingFrom)
      }
  }

  private let scheduler: SchedulerType

djds23

enum TrainLine { … }
enum TrainStation { … }
protocol TrainNetworkHandler {
  func departureTime(forLine: TrainLine, departingFrom: TrainStation) -> Observable<Date>
}

djds23

func waitForResourceAndButtonTap(
  resource: Observable<Bool>, 
  buttonTap: Observable<Void>
) -> Observable<Bool> {
  let emitOnlyAfterResourceHasArrived = Observable
    .combineLatest(
      buttonTap,
      resource.take(1)
  )

djds23

func simpleCombineStreams(
  resource: Observable<Bool>, 
  buttonTap: Observable<Void>
) -> Observable<Bool> {
  return buttonTap
    .withLatestFrom(resource)
}

djds23

struct FollowerNetworkingMock: FollowNetworkHandler {
  let mockFollowers: [User]
  let followResponse: Response
  func follow(user: User) -> Observable<Response> {
    return .just(followResponse)
  }
  func followers() -> Observable<[User]> {
    return .just(mockFollowers)
  }
}