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

The filter operator is used to filter out values emitted by an Observable that do not satisfy a specified condition. The operator takes a predicate function as an argument that is applied to each value emitted by the source Observable.

Here's an example of how to use the filter operator from the rxjs library in JavaScript:

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

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

const example = source.pipe(
  filter(num => num % 2 === 0)
);

example.subscribe(console.log); // output: 2, 4
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In this example, we created an Observable source that emits an array of numbers from 1 to 5. We then created a new Observable example using the filter operator to filter out odd numbers. Finally, we subscribed to example and logged the values emitted by it.

Note that the filter operator does not modify the source Observable, but returns a new Observable that emits only the filtered values.