NewEffect creates a side effect that runs immediately and re-runs whenever

any dependency changes.

 

Dependencies must be passed explicitly. The effect function should not

return anything; for effects that need cleanup use [NewEffectWithCleanup].

 

Example:

 

count := state.NewSignal(0)

 

eff := state.NewEffect(func() {

fmt.Println("count is", count.Get())

}, count.AsReadonly())

defer eff.Stop()

 

count.Set(5) // prints "count is 5"

func NewEffect(fn func(), deps ...any) EffectRef {
	return signals.Effect(fn, deps...)
}

NewEffectWithCleanup creates a side effect whose function returns a cleanup

callback.

 

The cleanup callback is called:

- Before the next execution of the effect

- When Stop is called

 

This is useful for canceling timers, closing connections, or removing

event listeners established by the effect.

 

Example:

 

interval := state.NewSignal(time.Second)

 

eff := state.NewEffectWithCleanup(func() func() {

ticker := time.NewTicker(interval.Get())

go func() {

for range ticker.C {

fmt.Println("tick")

}

}()

return func() { ticker.Stop() }

}, interval.AsReadonly())

defer eff.Stop()

func NewEffectWithCleanup(fn func() func(), deps ...any) EffectRef {
	return signals.EffectWithCleanup(fn, deps...)
}