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

The mapTo operator is used to map each value emitted by the source Observable to a static value, producing a new Observable that emits the mapped value instead of the original value. Here's how to use it with RxJS:

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

// create an observable that emits values
const source = of(1, 2, 3, 4, 5);

// apply the mapTo operator to each value emitted by the source
const example = source.pipe(mapTo('Hello World!'));

// output the results
example.subscribe(val => console.log(val)); // output: 'Hello World!', 'Hello World!', 'Hello World!', 'Hello World!', 'Hello World!'
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In this example, we create an Observable source that emits the numbers 1 through 5. We then use the mapTo operator to map each value emitted by source to the string 'Hello World!', producing a new Observable example. Finally, we subscribe to example and log each value emitted to the console, which will output the string 'Hello World!' five times.