Pipe RxJS observable to existing subject

Question

There is existing subject that is in use:

const fooSubject = new BehaviorSubject(null);

And there is another observable (another subject in

Answer 1

Since Subject is already an observer with methods next(), error() and complete() you can just subscribe it to any Observable:

const fooSubject = new BehaviorSubject(null);

const barSubject = new Subject();
barSubject.subscribe(fooSubject);

barSubject.next('bar');