how to use the asyncsubject function from the rxjs library in javascript

The AsyncSubject is a type of subject in RxJS library that only emits the last value from the source observable to its subscribers. It will wait until the source observable completes and then it will emit the last value to all subscribers.

Here is an example of how to use the AsyncSubject:

index.tsx
const { AsyncSubject } = require('rxjs');

// Create an AsyncSubject
const asyncSubject = new AsyncSubject();

// Subscribe to the AsyncSubject
asyncSubject.subscribe({
  next: value => console.log(`Received value: ${value}`),
  complete: () => console.log('AsyncSubject complete')
});

// Emit values to the AsyncSubject
asyncSubject.next(1);
asyncSubject.next(2);

// Complete the AsyncSubject
asyncSubject.complete();

// Output:
// Received value: 2
// AsyncSubject complete
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In the example above, we imported the AsyncSubject class from the RxJS library, then instantiated an AsyncSubject object. After that, we subscribed to the subject to receive emitted values. We then emitted two values using the next() method and finally called the complete() method to inform the AsyncSubject that we are done emitting values.

The output shows that only the last value (2) was emitted to the subscriber after the AsyncSubject completed.