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

To use the distinctUntilKeyChanged function from the RxJS library in JavaScript, first, you need to import it as an operator:

index.tsx
import { distinctUntilKeyChanged } from 'rxjs/operators';
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Then, you can use it with an observable:

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

const data = [
  { id: 1, name: 'John' },
  { id: 2, name: 'Jane' },
  { id: 3, name: 'Doe' },
  { id: 3, name: 'Doe' },
  { id: 4, name: 'Smith' }
];

from(data)
  .pipe(
    distinctUntilKeyChanged('id')
  )
  .subscribe(console.log);
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In this example, we have an array of objects representing users with id and name properties. We create an observable from the array using the from function from RxJS.

Then, we use the distinctUntilKeyChanged operator with the id property as a parameter. This will ensure that only values with different ids are emitted by the observable.

Finally, we subscribe to the observable and log the emitted values to the console.

This will output:

index.tsx
{ id: 1, name: 'John' }
{ id: 2, name: 'Jane' }
{ id: 3, name: 'Doe' }
{ id: 4, name: 'Smith' }
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