Pipe and select operators in RxJS

Question

I'm wondering whether the following two blocks of code behave in the same manner:

With pipe (from original ngrx sample):

pending$ = this.store.pipe(select(fromAuth.selectLoginPagePending));
error$ = this.store.pipe(select(fromAuth.selectLoginPageError));

And without one:

pending$ = this.store.select(fromAuth.selectLoginPagePending);
error$ = this.store.select(fromAuth.selectLoginPageError);

I've tested both and haven't noticed any apparent difference.

Thoughts?

Answer 1

Yes, you are right. Both

pending$ = this.store.pipe(select(fromAuth.selectLoginPagePending));
error$ = this.store.pipe(select(fromAuth.selectLoginPageError));

and

pending$ = this.store.select(fromAuth.selectLoginPagePending);
error$ = this.store.select(fromAuth.selectLoginPageError);

carry out the same function, which is to obtain a slice of the store state , as described on the NgRX documentation on selectors.

However, the pipe() utility allows you to chain the selector with RxJS pipeable operators, such as scan(), and filter(), allowing you to carry out other operations such as state transitions.