defaultIfEmpty
RxJS 5 defaultIfEmpty
HTML
<script src="https://npmcdn.com/@reactivex/[email protected]/dist/global/Rx.umd.js"></script>JavaScript
const empty = Rx.Observable.of();
//emit 'Observable.of() Empty!' when empty, else any values from source
const exampleOne = empty.defaultIfEmpty('Observable.of() Empty!');
//output: 'Observable.of() Empty!'
const subscribe = exampleOne.subscribe(val => console.log(val));