Ace the Rust Interview

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beginner · order 30

NLL ends the borrow before you think

borrow-nll-01Related book chapters: 6 (optional — this page is complete on its own)NLL

Slug: borrow-nll-01 · Paired reading: Chapter 6

Prompt

fn last_then_clear(v: &mut Vec<i32>) -> Option<i32> — copy out the last element, then clear() the vec. NLL ends the last() borrow before clear needs &mut.