component-store: An effect declared with type void does not accept a void observable

[Harpush]

Minimal reproduction of the bug/regression with instructions

An effect with void type argument cannot accept observables as opposed t other types.

Minimal reproduction of the bug/regression with instructions

Allow passing an observable of type void or nothing.

Versions of NgRx, Angular, Node, affected browser(s) and operating system(s)

Ngrx 13 with Angular 13

Other information

Originated from discord discussion: https://discord.com/channels/740557383109050469/740560647967866912/988876322086481933

I would be willing to submit a PR to fix this issue

• Yes
• No

[timdeschryver]

After some time thinking about this, I realized that (almost) all Observables have a return value.
So, to make this "fix" useful this this would also imply that all types should be accepted as argument?

For now, a workaround would be to create an unknown effect.

someEffect = effect<unknown>(...)

someEffect(eventEmitter)

The more I think about it, the more I think that this is desired:

• void => used for effects without arguments, effect()
• type => for effects that have a strict type, effect(1) or effect(Observable<string>)
• unknown => when you just want to trigger the effect, effect(Observable<unknown|any>)

[Harpush]

@timdeschryver Isn't it a bit misleading though? The unknown value will never be used but the effect will accept anything (number, string, etc...). Concerning void - if the argument will be optional wouldn't it solve both? You can pass nothing or an observable compared to number which require a number or observable of numbers.

If there is an observable the returns a number but the effect has no need for it - then unknown might work or just use number and ignore it.

Anyway currently unknown just break out of type checking accepting unknown and not observable of unknown.