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capture mode

How a closure holds a variable it uses: by borrowing it, borrowing it mutably, or taking it.

Each variable a closure uses is captured by shared reference, mutable reference, or by value, whichever is the least the body needs (unless move forces by value).

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Examples

  • || println!("welcome to {shop}") borrows shop, || stamps += 1 borrows stamps mutably, and a body with let archived = receipt; takes receipt by value.

See also

move closure Fn traits borrow checker
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