Guillaume Martres

This library uses macro annotations which don't exist in Dotty, but things like `@autoFunctorK trait Foo[F[_]]` should be rewritable as `trait Foo[F[_]] derives FunctorK` using https://dotty.epfl.ch/docs/reference/contextual/derivation.html. In fact it looks...

Out of curiosity, what part of cats-tagless requires generating arbitrary class implementations? I would have though that at least some part of cats-tagless could already be implemented today given that...

Would https://github.com/lampepfl/dotty/pull/11686 be relevant?

You can mix them yes, but you can't represent method with default parameters or methods with varargs losslessly as functions.

Well, someone has to go and try to port the macros to find that out :). That would be a good exercise since this feature is still experimental in the...

That stackoverflow is fixed in 3.1.1 but your build uses 3.1.0 for some reason.

Alternatively, I imagine cats 3.0.0 could use https://docs.scala-lang.org/scala3/reference/contextual/derivation.html which might also save people from writing all these instances :grin:

Which other problems? The documentation mentions avoiding the need for multiple implicit scopes but I don't think that's actually needed as mentioned in https://github.com/typelevel/cats/pull/4061#discussion_r760482994

FYI, https://github.com/lampepfl/xml-interpolator contains a new xml interpolator implementation for Dotty, which is mostly complete (its usage of scala-parser-combinators should either be replaced by fastparse, or by a hand-written recursive descent...

Dotty-only since it uses Dotty macros.