Return an empty Observable

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With the new syntax of RxJS 5.5+, this becomes as the following:

// RxJS 6
import { EMPTY, empty, of } from "rxjs";

// rxjs 5.5+ (<6)
import { empty } from "rxjs/observable/empty";
import { of } from "rxjs/observable/of";

empty(); // deprecated use EMPTY
EMPTY;
of({});

Just one thing to keep in mind, EMPTY completes the observable, so it won’t trigger next in your stream, but only completes. So if you have, for instance, tap, they might not get trigger as you wish (see an example below).

Whereas of({}) creates an Observable and emits next with a value of {} and then it completes the Observable.

E.g.:

EMPTY.pipe(
    tap(() => console.warn("i will not reach here, as i am complete"))
).subscribe();

of({}).pipe(
    tap(() => console.warn("i will reach here and complete"))
).subscribe();

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