Tracking Issue for `borrowed_buf_init`

[tgross35]

Feature gate: #![feature(borrowed_buf_init)]

This is a tracking issue for borrowed_buf_init

Public API

impl<'data, T> BorrowedBuf<'data, T> {
    pub fn is_init(&self) -> bool;
}

impl<'data, T: Copy> BorrowedBuf<'data, T> {
    pub unsafe fn set_init(&mut self) -> &mut Self;
}

impl<'a, T: Copy> BorrowedCursor<'a, T> {
    pub fn is_init(&self) -> bool;
    pub unsafe fn set_init(&mut self);
    pub fn advance_checked(&mut self, n: usize) -> &mut Self;
}

impl<'a> BorrowedCursor<'a, u8> {
    pub fn ensure_init(&mut self) -> &mut [u8];
}

Steps / History

• Implementation on the preexisting tracking issues: Tracking Issue for RFC 2930 (read-buf) #78485, Tracking Issue for core_io_borrowed_buf #117693
• Make ensure_init generic over T: Default: core: generalize BorrowedCursor::ensure_init #160432
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• Can the bounds for ensure_init be weakened to T: Default? Or should we have API more similar to [T: Clone]::fill(&mut self, value: T) / [T]::fill_with<F: FnMut() -> T>(&mut self, f: F)?

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩

[tgross35]

Created a new issue since this isn't in the proposed stabilization, and added an unresolved question that is probably worth checking.