ReplaySubject

by pointzerotwo

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/5.4.3/Rx.js"></script>

JavaScript

const user$ = new Rx.ReplaySubject(1);
//const user$ = new Rx.Subject(); 

user$.subscribe(val => console.log(val));

setTimeout(function() {
  user$.next('a');
  user$.next('b');
  user$.subscribe(val => console.log('new subscriber:', val));
  user$.next('c');
}, 1000);