Rust enables the Polonius Alpha borrow checker on nightly and targets stabilization this year
- Sources: primary, discussion
- Summary: The Rust project enabled Polonius Alpha on nightly and states stabilization is targeted for this year. The analysis is flow-sensitive, so borrows are tracked per control-flow path rather than per lexical region.
- Why it matters: Flow-sensitive analysis makes the get_mut_or_default pattern compile without a workaround, the first change to what borrowck accepts since NLL replaced AST borrowck in 2019.