RxJS - Observeable in flatMap function - Coding Blast - www.codingblast.com

rxjs-observable-flatMap-observable.ts

import {Observable} from 'rxjs';

let source = Observable
    .interval(100) // interval starts from 0
    .take(5) // take first 5
    // 0, 1, 2, 3, 4
    .flatMap(n => {
        let observable = Observable.of(n + 10);
        // we now have an observable here, not a number!
        return observable;
    });

source.subscribe((value) => {
    console.log('in next. Value: ', value);
});