Add .toBehaviorSubject() and .toReplaySubject() methods

[diestrin]

I find it really verbose to convert an observable to either beahvior or replay subjects.

Every time I need to do this I have to:

const replay$ = new Replay<string>();
source$.subscribe(replay$);

Wouldn't be better to have shortcuts for this? Like:

const replay$ = source$.toReplaySubject();
const behavior$ = source$.toBehaviorSubject('inital value');

I can get into the code and hack it and PR, but I'd like to hear the thoughts first. Maybe there's a reason not to have this?

Regards.

[diestrin]

Is publishBehavior the same thing?

[diestrin]

I'm trying to do the same thing with publishBehavior, but it still is a multi step process (now I need 3 lines, and 2 variables) and I can't seem to have access to the observable:

const connectable$ = source$.publishBehavior('initial value');

// this method is protected, and there's no other way to get access
// to the BehaviorSubject created
const behavior$ = connectable$.getSubject();

connectable$.connect();

[benlesh]

It looks like we missed putting a selector on publishBehavior like publish has.

However, you can do everything in one step with multicast:

source$.multicast(new ReplaySubject(3), replayed =>
  replayed.map(x => x + x); // do stuff here
)
.subscribe(x => console.log(x))

[benlesh]

Closing in favor of #2844 and #2845.

[diestrin]

Awesome, thanks :)

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.