This lesson helps you think in Reactive programming by explaining why it is a beneficial paradigm for programming. See how reactive programming helps you understand the dynamic behavior of a value evolving over time.
Hi Dave. Also in RxJS you can push new values into a stream, if that stream is a Subject. However, that is not anymore reactive programming. What I explained in this lesson was, in order to stay in the realm of reactive programming and reap its benefits, we shouldn't update/push a stream. Everything that can possibly change the stream should be defined at the time of declaration, regardless if that change is instantaneous at the time of declaration or if the change will come later in the future through some other Observable.
Hi Daniel. We could, but that has its problems too, watch this presentation to see why: https://www.youtube.com/watch?v=BfZpr0USIi4
Kostiantyn, all the dynamic updates should be specified in the declaration of the observable. That's the reactive approach. You don't need to know beforehand exactly what values, but you need to know from where will these dynamic values come from. If you want to change the values according to clicks, then you declare the observable with a dependency on the click observable, for example.