Closure Timers

Last updated: October 08, 2018


Timers with Closures


The ClosureTimers.wurst package wraps Warcraft III timer mechanics using Wurst closures. The usage of closures allows you to carry over data and save the callbacks in a variable.

While ClosureTimers are great and fit for most tasks, in performance critical situations, the TimedLoop module can yield better results.

Delayed actions

The most common usecase for timers is executing something after a given time, without stopping the execution of other code. To do this use the doAfter() function. A few examples:

// Destroy effect after 5 seconds
let eff = addEffect(Abilities.vengeanceMissile, ZERO2)
doAfter(5.) ->

// Inflict damage after time
let attacker = GetEventDamageSource()
let target = GetTriggerUnit()
doAfter(2.) ->
	attacker.damageTarget(target, 20)

Compared to vJass variants of timer data attachment you should immediately notice, that the data attachment with closures happens automatically. At creation, the closure will capture data used inside it, in this case eff and attacker, target respectively, so you can reference them later in the callback.

Behind the scenes ClosureTimers just use TimerUtils data attachment themselves.

Periodic actions

The other typical usecase for timers is periodical execution of a certain action. Use doPeriodically() or doPeriodicallyCounted.

doPeriodically(ANIMATION_PERIOD) cb ->
	if missiles.size() == 0
		destroy cb
		for missile in missiles

// Countdown
doPeriodicallyCounted(1, 3) cb ->
	print(cb.getCount().toString() + "..")

As you can see, in this variants the callback received the closure object as parameter, so you can destroy or modify it. You can also save the callback in a variable, to destroy it e.g. when the related unit dies.

class MyClass
	CallbackPeriodic cb

		cb = doPeriodically(0.5, () -> checkAura())

	function checkAura()

		destroy cb