This would be huge for Ruff.

ah, its parser part was not that much ready and I need to find how to add a soft-keyword concept to parser.

I hope this can help Ruff to support pattern matching and close the issue charliermarsh/ruff#282

The dream...

Sorry to double-post, but copying over my most recent comment from the related issue in Ruff:

I'd love to sponsor someone (financially, that is) to work on this issue (in RustPython). If you're interested, shoot me a DM on Twitter or email me at [email protected] :)

To be honest, after watching @andersk's work, I thought his way would be much better than my hacky local work.
I was going to add a mode to lexer to optionally generate a match token - which is not a good idea for either design or performance.
@andersk Do you have a plan to work on it? I think you are the one who is most close to the goal.