Combining Subjects without waiting for each to emit

Issue

I Have 4 Subjects that emit values on user Input

this.combine$ = zip(
  this.filterInputStore.selectedCurrenciesHandler,
  this.filterInputStore.searchInputHandler,
  this.filterInputStore.selectedTypesHandler,
  this.filterInputStore.selectedPrivacyOptionsHandler
).pipe(tap(() => { doSomething() }));

My Goal is to trigger the doSomething(), as soon as one of them emits a value.

Problem: All rxjs operators like zip or combineLatest require to wait until all subjects in it emit. This is extremely impractical if say i want to filter a list and want results even if i only use one filter. Is there a rxjs best practise for this?

Solution

I believe both merge or race would work. I prefer race because the method indicate that you're waiting for the first observable to emit (and win the race!). Also, race will trigger only ONCE, so your doSomething won't get executed multiple times.

Answered By - Nam