Tracking issue for #![feature(maybe_uninit_slice)] (original) (raw)

This is a tracking issue for the RFC "Deprecate uninitialized in favor of a new MaybeUninit type" (rust-lang/rfcs#1892).

Most of this has been stabilized, this issue now only tracks the below unstable methods.

Public API

impl [MaybeUninit] { pub unsafe fn assume_init_drop(&mut self); pub const unsafe fn assume_init_ref(&self) -> &[T]; pub const unsafe fn assume_init_mut(&mut self) -> &mut [T];

pub const fn slice_as_ptr(this: &[MaybeUninit<T>]) -> *const T;
pub const fn slice_as_mut_ptr(this: &mut [MaybeUninit<T>]) -> *mut T;

}

Steps / History

• Implementation
• Make slice methods inherent: Add inherent versions of MaybeUninit methods for slices #129259
• Ensure documentation has examples
• Final comment period (FCP)
• Stabilization PR

Unresolved Questions

• Should slice_as_ptr/slice_as_mut_ptr be methods (with some Self parameter) instead of functions?
• slice_as_ptr/slice_as_mut_ptr get rid of the slice length, so .add(n) needs to be used on the result instead of a safer [n]. See accepted ACP Remove MaybeUninit::slice_as_(mut_)ptr and optionally add *const/*mut MaybeUninit -> *const/*mut T type safe conversions libs-team#245 and its incomplete implementation Nuke slice_as{,_mut}_ptr methods of MaybeUninit #103133