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

The range function in rxjs library is used to create an observable sequence of numbers within a specified range. Here's how to use it:

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

// create an observable that emits numbers 1 to 10
const observable = range(1, 10);

// subscribe to the observable
observable.subscribe(number => {
  console.log(number);
});
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In the code above, we first import the range function from the rxjs library. Then we use it to create an observable that emits numbers 1 to 10. The first parameter 1 is the start of the range and the second parameter 10 is the number of values to emit. Finally, we subscribe to the observable using the subscribe method and log each emitted value to the console.

You can also apply operators to the observable sequence created by the range function. Here's an example that maps each emitted number to its square:

index.tsx
const { range } = require('rxjs');
const { map } = require('rxjs/operators');

// create an observable that emits squares of numbers 1 to 10
const observable = range(1, 10).pipe(
  map(number => number * number)
);

// subscribe to the observable
observable.subscribe(square => {
  console.log(square);
});
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In this code, we also import the map operator from the rxjs/operators module. We then apply the map operator to the observable sequence created by the range function using the pipe method. The map operator transforms each emitted number to its square. Finally, we subscribe to the new observable sequence and log each emitted squared value to the console.