Higher-Order Observables — Series 2

Preview — 3 of 10 questions

What do these options control?

javascript

source$.pipe(share({
  connector: () => new ReplaySubject(1),
  resetOnRefCountZero: false,
  resetOnError: true,
}))

Aconnector chooses the subject that multicasts — a ReplaySubject(1) here, which makes this equivalent to shareReplay(1); the reset flags decide whether the shared subscription is torn down when subscribers leave or when the source errors

Bconnector is the HTTP connection to reuse

CThe options only affect debugging output

DresetOnRefCountZero: false means the source is resubscribed for every new subscriber

When does the observable emit relative to the signal write?

javascript

count = signal(0);
count$ = toObservable(this.count);

ASynchronously, inside count.set()

BOnly when something subscribes, replaying every past value

CNever for the initial value

DAsynchronously: it is backed by an effect, so emissions are delivered when effects run, and several writes in the same tick can collapse into one emission of the final value

What does this change?

javascript

const a$ = of(Date.now());
const b$ = defer(() => of(Date.now()));

ANothing; of is already lazy

Ba$ captures the timestamp once, when the observable is created; b$ runs its factory per subscription, so each subscriber gets the time at its subscription

Cb$ emits continuously

Db$ caches the first subscriber's value for all later ones

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