This operator is analogous to the concat() operator, but it concatenates all observables inside an observable. This operator has the following signature:
As you can see, it does not receive any parameter as it will concatenate all observable within an observable. This behavior can be seen in the following example:
Rx.Observable.of( Rx.Observable.just(1), Rx.Observable.fromPromise(Promise.resolve(2)), Rx.Observable.of(3,4) ).concatAll() .subscribe((k)=>console.log(k));
In this example, we create an Observable using the of() method, containing three observables. The first only emits the value 1, the second only emits the value 2 (using a Promise), and the third emits two values ...