Tracking Issue for const Derefs

[fee1-dead]

Feature gate: #![feature(const_deref)]

This is a tracking issue for implementing const Deref{,Mut} in the standard library.

Public API

// alloc::borrow

impl<B: ?Sized + ToOwned> const Deref for Cow<'_, B>
where
    B::Owned: ~const Borrow<B> {
    type Target = B;
}

// core::mem::manually_drop
impl<T: ?Sized> const Deref for ManuallyDrop<T> {
    type Target = T;
}
impl<T: ?Sized> const DerefMut for ManuallyDrop<T> {
    type Target = T;
}

// core::ops::deref
impl<T: ?Sized> const Deref for &mut T {
    type Target = T;
}
impl<T: ?Sized> const Deref for &T {
    type Target = T;
}

Steps / History

• Implementation: Const Deref #88887
• Final comment period (FCP)
• Stabilization PR

Unresolved Questions

• None yet.

[RalfJung]

This got entirely removed in #110393.

[npmccallum]

I think this issue needs to be reopened. It is the only tracking issue for const_deref and there's definitely const_deref code in master.

[RalfJung]

No, the new implementation should use a new tracking issue.

[npmccallum]

@RalfJung my point is that the new implementation is already merged and already points to this issue.

[clarfonthey]

Yes, there are issues with the tracking issues for these traits and that is currently being fixed by #145279, which uses #143773 as its new tracking issue.

I'm currently not including these methods, but I can add those to my PR.