Tracking Issue for `[T; N]::resize(_with)` (feature `array_resize`)

[scottmcm]

Feature gate: #![feature(array_resize)]

This is a tracking issue for the resize and resize_with methods on arrays.

Like Vec::resize(_with), these extend for a larger size or truncate for a shorter one. Unlike Vec, these return a new array (because obviously one can't change the size of a fixed-size array in-place).

Public API

impl<T, const N: usize> [T; N] {
    pub fn resize<const NEW_LEN: usize>(self, value: T) -> [T; NEW_LEN];
    pub fn resize_with<const NEW_LEN: usize>(self, mut f: impl FnMut() -> T) -> [T; NEW_LEN];
}

Steps / History

• Implementation: Add resize(_with) and (try_)repeat(_with) for arrays #91506
• Final comment period (FCP)
• Stabilization PR

Unresolved Questions

• None yet.

[briansmith]

What is the motivation? concat! for arrays seems like an alternative that would allow the same with similar convenience and more generality.