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

To use the pairwise function from the RxJS library in JavaScript, you need to first import it from the RxJS library.

Here is an example of how to use the pairwise function:

import { from } from 'rxjs';
import { pairwise } from 'rxjs/operators';

const source = from([1, 2, 3, 4, 5]);

source.pipe(pairwise())
  .subscribe(console.log);
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In the above example, we first import the from function from the RxJS library to create an observable from an array. We also import the pairwise operator from the RxJS operators module.

We then create an observable using the from function with an array of numbers. We call the RxJS pipe method on the source observable to chain the pairwise operator. Finally, we subscribe to the observable and log the output to the console.

The pairwise operator merges pairs of consecutive emissions from the source observable and emits an array of the two most recent emissions. So the output of the above example would be:

index.tsx
[1, 2]
[2, 3]
[3, 4]
[4, 5]
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You can use the pairwise function with any observable that emits values, not just observables created using the from function.