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Starter#Promises#Polyfill
Promise.allSettled / race / any Polyfills
Implement the three Promise utility variants: allSettled (never rejects), race (first to settle wins), and any (first to resolve wins).
By modernDev2026-06-05Medium
These three are variations on Promise.all. Interviewers ask them together because the differences test whether you understand promise settling. allSettled never rejects — there is no reject call in its executor at all. race is tiny because the first resolve/reject wins automatically. any is the inverse of all: it resolves on the first success and only rejects if everything fails.
Goal: Implement all three variants. Focus on the structural difference between them — not just the code.
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