rust-lang/rust — pull request #19916 by SimonSapin (2014-12-16 12:11:09+00:00)
Title: `std::ascii` reform

See [RFC 486](https://github.com/rust-lang/rfcs/pull/486), #19908.

* Rename `to_ascii_{lower,upper}` to `to_ascii_{lower,upper}case`, per #14401
* Remove the `Ascii` type and associated traits: `AsciiCast`, `OwnedAsciiCast`, `AsciiStr`, `IntoBytes`, and `IntoString`.
* As a replacement, add `.is_ascii()` to `AsciiExt`, and implement `AsciiExt` for `u8` and `char`.

[breaking-change]