twittemb · March 15, 2020 18:42
diff --git a/spin-example-reactiveswift.swift b/spin-example-reactiveswift.swift
 // the State of the feedback loop
 struct Levels {
    let left: Int
    let right: Int
 }

 // the transition requests of the feedback loop
 enum Event {
    case increaseLeft
    case decreaseLeft 
    case increaseRight
    case decreaseRight
 }

 // the side effects of the feedback loop
 func leftEffect(inputLevels: Levels) -> SignalProducer<Event, Never> {
    // this is the stop condition to our Spin
    guard inputLevels.left != inputLevels.right else { return .empty }

    // this is the regulation for the left level
    if inputLevels.left < inputLevels.right {
        return SignalProducer(value: .increaseLeft)
    }  else {
        return SignalProducer(value: .decreaseLeft)
    }
 }

 func rightEffect(inputLevels: Levels) -> SignalProducer<Event, Never> {
    // this is the stop condition to our Spin
    guard inputLevels.left != inputLevels.right else { return .empty }

    // this is the regulation for the right level
    if inputLevels.right < inputLevels.left {
        return SignalProducer(value: .increaseRight)
    }  else {
        return SignalProducer(value: .decreaseRight)
    }
 }

 // the reducer of the feedback loop
 func levelsReducer(currentLevels: Levels, event: Event) -> Levels {

 	guard currentLevels.left != currentLevels.right else { return currentLevels }

 	switch event {
 	    case .decreaseLeft:
 	        return Levels(left: currentLevels.left-1, right: currentLevels.right)
 	    case .increaseLeft:
 	        return Levels(left: currentLevels.left+1, right: currentLevels.right)
 	    case .decreaseRight:
 	        return Levels(left: currentLevels.left, right: currentLevels.right-1)
 	    case .increaseRight:
 	        return Levels(left: currentLevels.left, right: currentLevels.right+1)
 	}
 }

 // The builder way to build the Spin
 let levelsSpin = Spinner
 	.initialState(Levels(left: 10, right: 20))
 	.feedback(Feedback(effect: leftEffect))
 	.feedback(Feedback(effect: rightEffect))
 	.reducer(Reducer(levelsReducer))

 // The declarative way to build the Spin
 let levelsSpin = ReactiveSpin(initialState: Levels(left: 10, right: 20),
                              reducer: Reducer(levelsReducer)) {
    Feedback(effect: leftEffect)
    Feedback(effect: rightEffect)
 }

 // to make a reactive stream from the Spin
 SignalProducer.stream(from: levelsSpin)
	// the State of the feedback loop
	struct Levels {
	let left: Int
	let right: Int
	}

	// the transition requests of the feedback loop
	enum Event {
	case increaseLeft
	case decreaseLeft
	case increaseRight
	case decreaseRight
	}

	// the side effects of the feedback loop
	func leftEffect(inputLevels: Levels) -> SignalProducer<Event, Never> {
	// this is the stop condition to our Spin
	guard inputLevels.left != inputLevels.right else { return .empty }

	// this is the regulation for the left level
	if inputLevels.left < inputLevels.right {
	return SignalProducer(value: .increaseLeft)
	} else {
	return SignalProducer(value: .decreaseLeft)
	}
	}

	func rightEffect(inputLevels: Levels) -> SignalProducer<Event, Never> {
	// this is the stop condition to our Spin
	guard inputLevels.left != inputLevels.right else { return .empty }

	// this is the regulation for the right level
	if inputLevels.right < inputLevels.left {
	return SignalProducer(value: .increaseRight)
	} else {
	return SignalProducer(value: .decreaseRight)
	}
	}

	// the reducer of the feedback loop
	func levelsReducer(currentLevels: Levels, event: Event) -> Levels {

	guard currentLevels.left != currentLevels.right else { return currentLevels }

	switch event {
	case .decreaseLeft:
	return Levels(left: currentLevels.left-1, right: currentLevels.right)
	case .increaseLeft:
	return Levels(left: currentLevels.left+1, right: currentLevels.right)
	case .decreaseRight:
	return Levels(left: currentLevels.left, right: currentLevels.right-1)
	case .increaseRight:
	return Levels(left: currentLevels.left, right: currentLevels.right+1)
	}
	}

	// The builder way to build the Spin
	let levelsSpin = Spinner
	.initialState(Levels(left: 10, right: 20))
	.feedback(Feedback(effect: leftEffect))
	.feedback(Feedback(effect: rightEffect))
	.reducer(Reducer(levelsReducer))

	// The declarative way to build the Spin
	let levelsSpin = ReactiveSpin(initialState: Levels(left: 10, right: 20),
	reducer: Reducer(levelsReducer)) {
	Feedback(effect: leftEffect)
	Feedback(effect: rightEffect)
	}

	// to make a reactive stream from the Spin
	SignalProducer.stream(from: levelsSpin)