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What is the difference between take(1) and first() operators in RxJS?

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01

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Compare RxJS termination operators.

rxjsoperators
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take(1) completes the observable after the first emission. first() also completes after the first emission but throws an EmptyError if the stream completes without emitting any value (unless a default/predicate is supplied).

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04

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Behavior differences on empty streams
import { EMPTY } from 'rxjs';
import { take, first } from 'rxjs/operators';

EMPTY.pipe(
  take(1)
).subscribe({
  next: val => console.log('Value:', val),
  complete: () => console.log('Completed cleanly!')
});

EMPTY.pipe(
  first()
).subscribe({
  next: val => console.log('Value:', val),
  error: err => console.log('Error caught:', err)
});
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