What is take, skip, takeUntil, combineLatest and pipe in observables?

These are operators in the RxJS library, which is commonly used in Angular for working with observables.

• take: The take operator limits the number of emissions from an observable by completing the observable after a specified number of emissions have been received.
• skip: The skip operator skips the first n emissions from an observable and then emits all remaining emissions.
• takeUntil: The takeUntil operator is used to stop emitting values from the source observable when a notifier observable emits a value.
• combineLatest: The combineLatest operator combines the latest values from multiple observables into a single observable, emitting an array of values whenever any of the source observables emit a new value.
• pipe: The pipe operator is used to chain together a series of operators to transform or manipulate an observable.

Here’s an example that demonstrates the use of these operators:

import { of, interval } from 'rxjs';
import { take, skip, takeUntil, combineLatest, pipe } from 'rxjs/operators';

const source1 = of(1, 2, 3, 4, 5);
const source2 = interval(1000).pipe(take(5));

combineLatest(source1, source2)
  .pipe(
    takeUntil(interval(3000)),
    skip(2),
    take(2),
    pipe(combine => combine.reduce((acc, curr) => acc + curr, 0))
  )
  .subscribe(x => console.log(x));

In this example, two observables source1 and source2 are created. source1 is an observable that emits the values 1, 2, 3, 4, and 5. source2 is an interval observable that emits values every second and takes 5 values. The combineLatest operator is used to combine the latest values from both observables into a single observable. This combined observable is then passed through a series of operators including takeUntil, skip, take, and pipe. The final result is an observable that emits the sum of the last two values after 3 seconds have passed.