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// RxJS v6+import { AsyncSubject } from 'rxjs';const sub = new AsyncSubject();sub.subscribe(console.log);sub.next(123); //nothing loggedsub.subscribe(console.log);sub.next(456); //nothing loggedsub.complete(); //456, 456 logged by both subscribers
📰 - Official docs
📁 Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/AsyncSubject.ts