Repository: rust
Issue: Tracking Issue for `{char, u8}::is_ascii_octdigit`
Labels: T-libs-api,C-tracking-issue

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Feature gate: `#![feature(is_ascii_octdigit)]`

This is a tracking issue for two new methods `char::is_ascii_octdigit` and `u8::is_ascii_octdigit`, which, in the same vein as `is_ascii_hexdigit`, checks if a value is an ASCII octal digit (`'0'..='7'`).

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This is a shorthand for `{char, u8}::is_digit(self, 8)`. Prior discussion on [irlo](https://internals.rust-lang.org/t/new-api-char-is-ascii-octdigit/17306).

### Public API

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```rust
// core::char

impl char {
    pub fn is_ascii_octdigit(self) -> bool;
}

// core::num

impl u8 {
    pub fn is_ascii_octdigit(self) -> bool;
}
```

### Steps / History

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- [x] Implementation: https://github.com/rust-lang/rust/pull/101308
- [ ] Final comment period (FCP)[^1]
- [ ] Stabilization PR

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### Unresolved Questions

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- None yet.

[^1]: https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html


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