pub const FRONTEND_VERSION: &str = "rust-lexer-v1";Expand description
Version tag of this frontend, used as a fingerprint input. Bump it whenever a change alters the token stream or unit boundaries for unchanged input.
Bumped with the parser it is built on. A newer parser can classify a token differently — a word that was an identifier becoming a keyword is the usual way — and fingerprints carry this version so that streams produced under rules that may disagree are never merged on the strength of an equal hash.