I know I said tomorrow, but this was one of those things that nagged at me and I ended up just finding 2 examples that I thought it could negatively affect, evaluated them, and it did not. it shouldn’t be a problem for intersections. The remaining concern from me is on ... allowing incompatible kwarg use. I don’t think it’s something that is clearly specified right now. While I’d prefer if we don’t allow it, and I think there’s a rationale that works for this, I’m fine with the outcome being allowing it as long as it’s clearly specified.
Edit: see comment here for the full related context, the most relevant part is below. It took me more to piece together what wasn’t sitting right with me…
The safe subtyping of gradual types in general is more complicated than we have language for.