ohm VS codemod

Building an interpreter or a compiler from a grammar is an interesting idea. I can't immediately see how to go about it - the grammar would need to match on SSA or similar.

The examples have a lisp-like interpreter at https://github.com/ohmjs/ohm/blob/main/examples/simple-lisp/... which definitely uses a grammar for parsing and might use a generic AST representation.

Will have to think more - a grammar might be a worthwhile way to specify a nanopass style compiler pipeline.

Look for OMeta and its successor Ohm.

One more suggestion: Maybe create your own scripting-language using Ohm? The project works in JavaScript, so whatever you created would sit on top of your existing APIs.

OMeta and its successor ohm might provide some interesting ideas.

Always fun to find the first commit:

https://github.com/harc/ohm/commit/4611bf63c5ecb90d782112d68...

2014

Neat tool. I write parsers by hand though. More fun, and you can be a lot sleazier.

This is new to me, sounds interesting!

I once used Codemod [0] to migrate an old JS codebase. Would this be a use case for Ohm as well?

[0] https://github.com/facebookarchive/codemod

That differs but is a reasonable understanding. I’m instead referring to automations that perform large scale refactoring as handled by Facebook, who would be contributing to this effort.

https://github.com/facebookarchive/codemod

It sounds like what you are describing is what’s known as poly fills which convert code into a variant that maximizes function across implementations which isn’t really applicable here.

That's why I've been working on a tool that automatically upgrades major versions of libraries with breaking changes, the idea is to simplify the process and save developers time and effort by having a bank of transformers (using codemod & jscodeshift) and open source them:

What they did appears similar to https://github.com/facebook/codemod.

I think codemod is probably one such tool: https://github.com/facebook/codemod