Tracking Issue for `unsigned_signed_diff`

[davidzeng0]

Feature gate: #![feature(unsigned_signed_diff)]

This is a tracking issue for rust-lang/libs-team#381

Public API

impl uX {
	pub const fn checked_signed_diff(self, rhs: Self) -> Option<iX>;
}

Steps / History

• Implementation: Implement unsigned_signed_diff #126042
• Final comment period (FCP)¹
• Stabilization PR: Stabilize unsigned_signed_diff feature #144900

Unresolved Questions

• None yet.

Footnotes

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

[davidzeng0]

For completeness, I could also implement rust-lang/libs-team#381 (comment)

impl iX {
    fn checked_unsigned_diff(self, rhs: Self) -> Option<uX>;
}

[pitaj]

checked_unsigned_diff should be under a separate feature and proposed as a new ACP.

Also, the overflowing, wrapping, saturating, and strict versions of this function are not implemented yet.

[loudjanilef]

Hi,
In the the associated PR #126042, the author was asked to remove the overflowing, wrapping, and saturating versions.
The associated PR was added to the 1.82 milestone and the 1.87 is now in beta.
There was no activity on this issue for a long time, should this feature enter in FCP?

[loudjanilef]

Hi @Amanieu
Allow me to ping you here as you accepted the original PR #126042
Should this feature enter FCP ?
Which steps would be needed ?

[Amanieu]

I updated the tracking issue to indicate that only checked_signed_diff is covered by this feature.

@rfcbot merge

[rfcbot]

Team member @Amanieu has proposed to merge this. The next step is review by the rest of the tagged team members:

• @Amanieu
• @BurntSushi
• @dtolnay
• @joshtriplett
• @m-ou-se

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.