Ace the Rust Interview

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advanced · order 152

Rc held across await

async-send-01Related book chapters: 13 (optional — this page is complete on its own)Sendawait

Slug: async-send-01 · Paired reading: Chapter 13

Prompt

Export async fn cached_len_fixed() -> usize that uses Rc before an await then drops it (book fix). Include local YieldOnce. Provide fn assert_send<F: Future + Send>(_: F) for the test.