b95fd857fe
Optimize `TokenKind::clone`. `TokenKind` would impl `Copy` if it weren't for `TokenKind::Interpolated`. This commit makes `clone` reflect that. r? `@ghost`
The rustc_ast crate contains those things concerned purely with syntax
– that is, the AST ("abstract syntax tree"), along with some definitions for tokens and token streams, data structures/traits for mutating ASTs, and shared definitions for other AST-related parts of the compiler (like the lexer and macro-expansion).
For more information about how these things work in rustc, see the rustc dev guide: