MediumEvent Loop & Promises💻 Output Question

Promise.all preserves order

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Hint

Promise.all preserves input order in results regardless of which promise resolves first.

What does this output?

Promise.all([
  Promise.resolve(1),
  Promise.resolve(2),
  Promise.resolve(3),
]).then(values => console.log(values.join(',')));

Correct Output

1,2,3

Why this output?

Explanation: Promise.all waits for all and resolves with an array of values in the original order.

Key Insight: Promise.all preserves input order in results regardless of which promise resolves first.

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