This crate can split Vec in half, with the front part being &mut [T], and the back part being able to perform push, pop etc

Examples

use tailvec::{TailVec, SplitTail};

let mut vec = vec![1, 2, 3, 4];
vec.reserve_exact(3);
assert_eq!(vec.capacity(), 7);

let (left, mut rest) = vec.split_tail(2);
assert_eq!(left, &mut [1, 2]);
assert_eq!(rest, &mut [3, 4]);

assert_eq!(rest.push(5), Ok(()));
assert_eq!(rest, &mut [3, 4, 5]);

assert_eq!(rest.push(6), Ok(()));
assert_eq!(rest, &mut [3, 4, 5, 6]);

assert_eq!(rest.push(7), Ok(()));
assert_eq!(rest, &mut [3, 4, 5, 6, 7]);

assert_eq!(rest.push(8), Err(8)); // overflow of capacity
assert_eq!(rest, &mut [3, 4, 5, 6, 7]);

assert_eq!(rest.pop(), Some(7));
assert_eq!(rest, &mut [3, 4, 5, 6]);

drop(rest); // drop guard
assert_eq!(vec, [1, 2, 3, 4, 5, 6])

Safe

• miri has passed