Quiz · 3 questions
⚡ Async & Promises — Typed Concurrency
Promise<T>, async/await, async iterables, Promise.all, error handling
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Quiz
01What's the return type of
async function foo(): string?Hint
Hover an async function with no annotated return type — TS will infer Promise<T> based on what you return.
02What does
Promise.all([p1, p2]) return at the type level?Hint
Destructure:
const [a, b] = await Promise.all([fetchA(), fetchB()]). a and b have distinct, correctly-inferred types.03What's the type of
e in try { ... } catch (e) { ... }?Hint
Try
throw 'oops' in one branch and throw new Error('oops') in another. Both reach catch, but e could be either.Comments 0
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