Rxjs quiz

Test your Rxjs knowledge with a free interactive quiz — 50 questions with answers and explanations. No signup needed to play.

What does `merge(a, b)` do?

1. What does `merge(a, b)` do?
2. How do you concatenate two Observables sequentially?
3. A subscription returned by `.subscribe()` is:
4. What does a `Subject` give you over a plain Observable?
5. `mapTo(value)` is similar to `map(() => value)`. When use it?
6. How do you handle errors inside a stream?
7. How do you start an Observable?
8. `debounceTime(300)` — what does it do?
9. `tap(fn)` is used for:
10. `distinctUntilChanged()` — what does it do?
11. What does `map(fn)` do?
12. `from([1, 2, 3])` vs `of([1, 2, 3])` — what is the difference?

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