what is the practical purpose of the Observable.never() function?

Rxjava has a method Observable.never(), that creates an empty observable, that never completes and never emits anything.

What is the purpose of that specific observable?

What is Observable Never?

An Observable that emits no items to the Observer and never completes.

How do you check if an Observable is empty?

The RxJS isEmpty() operator returns an observable with a Boolean value indicating whether the observable was empty or not. It returns an output as true if the source observable is empty; otherwise, false.

Why would you use RxJS?

RxJS is one of the key libraries each modern JavaScript developer should have in his kit. It's a library that helps developers simplify the process of composing callback-based or asynchronous code.

The main purpose is to prevent completing a stream or provide non-emitting Observable to operators that otherwise react to signals of secondary sources (for example, window, takeUntil). In addition, it is great for testing timeout with sequences.