General
An exploration of macro systems across languages, highlighting the danger of C-style macro expansion and the safety benefits of AST-based, hygienic macros in Lisp, Scheme, and Racket. It also surveys macro implementations in Julia, Elixir, and Rust, and ends with practical guidance for building robust macro-based abstractions. The piece emphasizes phase separation, hygiene, and good error messaging as keys to safe macro design.