Develop Macros in Rust May 15, 2021 Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement! Useful Crates for Macro Development¶syn¶Syn is a parsing library for parsing a stream of Rust tokens into a syntax tree of Rust source code. quote¶Quote provides the quote! macro for turning Rust syntax tree data structures into tokens of source code.