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Starter#Promises#Polyfill
Promise.all Polyfill
Implement Promise.all from scratch: resolve with an ordered results array when all settle, reject immediately on the first rejection.
By modernDev2026-06-05Medium
Promise.all executes all promises concurrently and resolves with an array of results in input order. If any one rejects, the whole thing rejects immediately. The ordering detail is the trap: because promises settle at different times, you must write to the original index, not push.
Goal: Implement Promise.myAll with correct ordering and fail-fast rejection.
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