Tracking Issue for `const_make_ascii`

[bjoernager]

Feature gate: #![feature(const_make_ascii)]

This is a tracking issue for marking the make_ascii_uppercase and make_ascii_lowercase methods in char, u8, [u8], and str as "const."

Public API

impl char {
    pub const fn make_ascii_uppercase(&mut self);

    pub const fn make_ascii_lowercase(&mut self);
}

impl u8 {
    pub const fn make_ascii_uppercase(&mut self);

    pub const fn make_ascii_lowercase(&mut self);
}

impl [u8] {
    pub const fn make_ascii_uppercase(&mut self);

    pub const fn make_ascii_lowercase(&mut self);
}

impl str {
    pub const fn make_ascii_uppercase(&mut self);

    pub const fn make_ascii_lowercase(&mut self);
}

Steps / History

• Implementation for char: Mark char::make_ascii_uppercase and char::make_ascii_lowercase as const. #130697
• Implementation for u8: Mark u8::make_ascii_uppercase and u8::make_ascii_lowercase as const. #130713
• Implementation for [u8] and str: Mark make_ascii_uppercase and make_ascii_lowercase in [u8] and str as const. #130738
• Final comment period (FCP)
• Stabilization PR: Stabilise const_make_ascii. #131496

Unresolved Questions

• None yet.

[dtolnay]

@rust-lang/libs-api:
@rfcbot fcp merge

to_ascii_uppercase/to_ascii_lowercase have been stable in const since 1.52. make_ascii_uppercase/make_ascii_lowercase are unblocked now by the stabilization of #57349.

[rfcbot]

Team member @dtolnay 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.

[okaneco]

Can the u8 methods be included in this?
https://doc.rust-lang.org/stable/std/primitive.u8.html#method.make_ascii_lowercase
https://doc.rust-lang.org/stable/std/primitive.u8.html#method.make_ascii_uppercase

Similarly const stable u8::to_ascii_uppercase/u8::to_ascii_lowercase since 1.52.

[bjoernager]

Yes, that sounds like a good idea. I'll try adding another PR later.