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

To use the combineAll function from the RxJS library, first you need to install RxJS using npm. You can do this by running the following command in your project's root directory:

npm install rxjs

Once you have installed RxJS, you need to import the combineAll function in your JavaScript file. You can do this by adding the following line at the top of your file:

index.tsx
import { fromEvent, interval } from 'rxjs';
import { map, take } from 'rxjs/operators';
import { combineAll } from 'rxjs/operators';
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Now you can use the combineAll function in your code. The combineAll function takes an observable of observables as input and returns an observable that emits an array of values from each source observable every time any of the source observables emits a value.

Here's an example of using combineAll to combine two observables:

index.tsx
const source1 = interval(1000).pipe(map(x => 'Source 1: ' + x), take(5));
const source2 = interval(500).pipe(map(x => 'Source 2: ' + x), take(10));
const combined = from([source1, source2]).pipe(combineAll());
combined.subscribe(x => console.log(x));
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In this example, interval is used to create two observables that emit values every 1 second and every 0.5 seconds respectively. map is used to transform the emitted values to strings that indicate which source the value came from. take is used to limit the number of emitted values from each observable. from is used to create a higher-order observable that combines the two source observables into a single observable of observables. Finally, combineAll is used to combine all the source observables and emit an array of values every time any of the source observables emits a value. The output of the code will be:

index.tsx
["Source 1: 0", "Source 2: 0"]
["Source 1: 0", "Source 2: 1"]
["Source 1: 1", "Source 2: 1"]
["Source 1: 0", "Source 2: 2"]
["Source 1: 1", "Source 2: 2"]
["Source 1: 2", "Source 2: 2"]
["Source 1: 0", "Source 2: 3"]
["Source 1: 1", "Source 2: 3"]
["Source 1: 2", "Source 2: 3"]
["Source 1: 3", "Source 2: 3"]
["Source 1: 0", "Source 2: 4"]
["Source 1: 1", "Source 2: 4"]
["Source 1: 2", "Source 2: 4"]
["Source 1: 3", "Source 2: 4"]
["Source 1: 4", "Source 2: 4"]
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