Also in Rust 1.85, a new #[diagnostic::do_not_recommend] attribute is a hint to the compiler not to show the annotated trait implementation as part of a diagnostic message. For library authors, this makes it possible to keep the compiler from making suggestions that may be misleading or unhelpful. The compiler in Rust 1.85 also removes the unstable flag, -Zpolymorphize. And panics in the standard library now have a leading /library in their path.
Stabilized APIs such as BuildHasherDefault::new, ptr::fn_addr_eq, and Unsigned {integer}::midpoint feature in Rust 1.85, along with a new tuple extension. Previous versions of Rust implemented convenience traits for iterators of (T, U) tuple pairs to behave like Iterator::unzip, with Extend in Rust 1.56 and FromIterator in Rust 1.79. These have been extended to more tuple lengths, from singleton (T,) through to 12 items long, (T1, T2, .., T11, T12).
With Rust 2024, Rust proponents are offering the largest edition of the language ever released. These editions are a mechanism for opt-in changes that might otherwise present a backward compatibility risk, the team said. A guide has been set up for transitioning projects to the 2024 edition.
