Motivate - Reversible Animation Chaining

Chain Animations in Swift with operators

What it Replaces

What Motivate does is turn this long chain of animations, set to fire one animation after the other completes:

func longFormChainedSyntax(){
    UIView.animateWithDuration(1.0, animations: { print("1") }, completion: { _ in
        
        UIView.animateWithDuration(1.0, animations: { print("2") }, completion: { _ in
            
            UIView.animateWithDuration(1.0, animations: { print("3") }, completion: nil)
        })
    })
}

into this much more readable syntax:

func Motivate(time t:Double, delay d:Double = 0.0, e: EmptyFunc) -> TimedPairWrapper

//USAGE
func shortFormChainedSyntax(){
    Motivate(time: 1.0){
        print("1\n")
    }
    <> Motivate(time: 2.0){
        print("2\n")
    }
    <> Motivate(time: 3.0){
        print("3\n")
    }
}

Usage

First use Motivate to build a TimedPair with a duration as time, optionally delay and a function to animate

let a = Motivate(time: 1.5, delay: 1.0) { print("1\n") }

Chain TimedPair animations together with the <> operator, which calls the next animation, on the completion of the previous.

         Motivate(time: 1.5) { print("1\n") }
      <> Motivate(time: 2.5) { print("2\n") }
      <> Motivate(time: 3.5) { print("3\n") }

Reversability

Using a "by" quantity type specification you can now reverse stored animations with runReverse().

    func Motivate(time t:Double, delay d:Double = 0.0, _ e: TimedPair...) -> TimedPairWrapper
    
    ////USAGE
    let animation =
            Motivate(
                time: 3.0,
                button1.byX(-20),
                button2.byX(-20)
            )
            <> Motivate(
                time: 1.0,
                button1.byX(-30),
                button2.byX(-30)
            )
         
    animation.runReverse()

### Looping

runLoop and forwardReverse() temporarily removed in current version