bip

bip (Box in place) provides a fully generic in-place map for the Box type, taking care to be panic-safe and not leak memory.

Example:

let x: Box<i32> = Box::new(1);
let y: Box<f32> = bip::map_in_place(y, |x| x as f32 + 1.0);

// y uses the same allocation as x

Documentation