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

The bufferToggle operator in RxJS is used to toggle between opening and closing buffer observables based on signals from another observable. It is very useful in scenarios where you need to accumulate values from a source observable until a certain condition is met.

Here is an example usage of bufferToggle:

index.tsx
import { fromEvent } from 'rxjs';
import { bufferToggle } from 'rxjs/operators';

const source = fromEvent(document, 'click');
const opening = fromEvent(document.getElementById('open'), 'click');
const closing = fromEvent(document.getElementById('close'), 'click');

source.pipe(
  bufferToggle(opening, () => closing)
).subscribe(val => console.log(val));
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In this example, we have a source observable source that emits events when a user clicks anywhere on the document. We are using the bufferToggle operator to accumulate these events into arrays when the user clicks the #open element and stops accumulation when they click the #close element.

The first argument to bufferToggle is the opening observable, which fires when buffering should begin. In this case, it is a click event on the #open element. The second argument is a function that returns a closing observable, which fires when buffering should end. In this case, it is a click event on the #close element.

The bufferToggle operator returns a new observable that emits an array of buffered values each time the closing observable emits.

You can use bufferToggle to implement features like drag-and-drop, where you need to buffer mouse events until the user releases the mouse button.