syntex

There's also rustlex [1] that have been around for a while and provides rust stable v1.0 support through syntex [2]. I use it for a handlebars implementation [3]. [1] https://github.com/LeoTestard/rustlex [2] https://github.com/erickt/rust-syntex [3] https://github.com/nicolas-cherel/rumblebars

It's interesting to see how Maud's approach uses syntax extensions, in contrast to the less-powerful (but more stable) macro-based approach that Horrorshow uses: https://users.rust-lang.org/t/horrorshow-a-no-longer-poc-htm... I also wonder if Maud could benefit from the Syntex library (https://github.com/erickt/rust-syntex) which uses a fork of Rust's (currently unstable) parsing library to enable syntax extensions to work on the stable Rust release via code generation.