As an exercise, I did one two years ago for pi-forall. That had a small scanner for the off-sides stuff. I lost steam after I got it working (and needed to add

As an exercise, I did one two years ago for pi-forall. That had a small scanner for the off-sides stuff. I lost steam after I got it working (and needed to add a bunch of rules). I think I was mainly trying to see if I could get tree-sitter to do off-sides (haskell-like indentation). One issue that I remember was the web application to test the grammar needed an exact version of the emscripten stuff. And I had to sort out what that version was myself.