rx.js, 'of' argument scheduler

argument scheduler.js

let Rx = window['rxjs'];
const {of,
       queueScheduler,
       asapScheduler,
       asyncScheduler,
       animationFrameScheduler
      } = Rx;
const {observeOn, tap} = Rx.operators;
console.clear();

setTimeout(() => console.log('It will runs just after this Macrotask'))

 let source$ = of(1, 2, 3, asyncScheduler).pipe(
   tap((v) => console.log('tap ', v))
 )

source$.subscribe((v) => {
  console.log('Value ', v);
  Promise.resolve().then(() => console.log('Microtask value ', v));
  setTimeout(() => console.log('MAcrotask value ', v), 0);
});