JS Built-ins
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ArrayArray.fromAsyncadvanced

Array.fromAsync() — works with sync iterables

📖 Usage Example
const set = new Set([10, 20, 30])
const arr = await Array.fromAsync(set)
// → [10, 20, 30]

Array.fromAsync() also works with synchronous iterables like Set or Map.

Array.fromAsync() — sync iterable input

Array.fromAsync() is not limited to async iterables. It also accepts sync iterables (like plain arrays or Sets), returning a Promise that resolves to the collected elements. This makes it a drop-in for Array.from when you need a Promise regardless.

This exercise demonstrates the pattern synchronously using Array.from on a Set.

Challenge: Implement syncToArray that converts a Set<number> to an array using Array.from.

syncToArray(new Set([1, 2, 3])) // → [1, 2, 3]
💡 Hints (2)
  • • `Array.fromAsync` wraps the result in a Promise even for sync inputs.
  • • `Array.from` and `Array.fromAsync` accept any iterable (arrays, Sets, Maps, generators, strings).