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Async · easy

13. Promises and Combinators

Promise lifecycle and combinator methods.

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Promises represent asynchronous operations (pending, fulfilled, rejected). Combinators like `Promise.all`, `Promise.allSettled`, and `Promise.race` orchestrate concurrent actions.

js
const [bal, block] = await Promise.all([getBalance(), getBlock()]);

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  1. 1. Which combinator never rejects even if all promises fail?

  2. 2. How many times can a promise settle?

  3. 3. What happens when one promise rejects in Promise.all?

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