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advanced · order 159

The stale-waker hang

async-stale-01Related book chapters: 24 (optional — this page is complete on its own)stale-waker

Slug: async-stale-01 · Paired reading: Chapter 24

Prompt

Implement StaleWakerFuture (caches waker only on first poll — wrong) and FreshWakerFuture (always wake_by_ref the current cx). Also CountingWaker + block_on. Fresh must complete under block_on; Stale's second poll with a new CountingWaker must not wake the second.