Sharing this post I wrote up a few days ago for cleaning up my code and reducing token costs:

https://blog.giovanh.com/blog/2022/12/11/jinja2-as-a-pico-8-preprocessor/

In summary:

• Constants would be a very useful language feature to have
• Pico-8 doesn't have it and doesn't let you extend its preprocessor
• You can roll your own and it works great