Unicode identifiers (#322)

[mattiase]

Actually the compiler restricts identifiers to Latin-9 but it's a start, and I see no reason to hold back here.
(There are a couple of housekeeping patches here too. I could put them in a separate PR if you like.)

[monnier]

The CI doesn't seem happy, but other than that it looks OK to me. Can you point to the OCaml doc specifying the Unicode support? Is it possible to use UTF-8 encoding?

[mattiase]

It's new in OCaml 5.3.0; see the language manual and ocaml/ocaml#11736, ocaml/ocaml#12664, ocaml/ocaml#13628. I've verified that the CI grumpiness is nothing that wasn't there before (we really should do something about that).

To editorialise a bit, I think Unicode identifiers is an underrated feature, especially for teaching: any cognitive barriers removed for your students helps, even at uni+ level. I hope it can be extended to more scripts, even unicameral ones with some effort.

[mattiase]

To be clear, the encoding is always UTF-8.

[monnier]

Cool. I hadn't paid attention to the changes from latin-1 eons ago. 👍

[mattiase]

Anything left to do? I can't push this myself.
The CI errors are unrelated (from 10bfb61, see #317).

[monnier]

Anything left to do? I can't push this myself.

Oops, sorry, pushed.

[mattiase]

Thank you. Push the CHANGES.md part (#324) too? I forgot we maintained that file as well.

[monnier]

Thank you. Push the CHANGES.md part (#324) too? I forgot we maintained that file as well.

Done, thanks