[Solved] What is wrong with this forkJoin usage?import { forkJoin, interval } from 'rxjs'; const obs1 = interval(1000); const obs2 = interval(2000); forkJoin([obs1, obs2]).subscribe(console.log); | Angular

Angular - RxJS Operators

What is wrong with this forkJoin usage?

import { forkJoin, interval } from 'rxjs';

const obs1 = interval(1000);
const obs2 = interval(2000);

forkJoin([obs1, obs2]).subscribe(console.log);

AforkJoin will never emit because interval observables never complete

BforkJoin requires observables to emit strings only

Cinterval cannot be used with forkJoin due to timing issues

Dsubscribe callback is missing parentheses

Step-by-Step Solution

Solution:

Step 1: Understand interval observable behavior
interval creates an observable that emits indefinitely and never completes on its own.
Step 2: forkJoin requires completion
forkJoin waits for all observables to complete before emitting, so with infinite observables it never emits.
Final Answer:
forkJoin will never emit because interval observables never complete -> Option A
Quick Check:
forkJoin requires completion = B [OK]

Quick Trick: forkJoin waits for completion; infinite observables block emission [OK]

Common Mistakes:

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What is wrong with this forkJoin usage?