Expand Unicode characters allowed in identifiers


Currently Unicode subscripts are allowed in identifiers, but superscripts are not. I am in the process of writing some math heavy code, and superscripts and subscripts would make the code look a lot nicer. Haskell currently supports all characters in the Lm category [1]. Are there any interest in changing Rust to support those characters as well?

Would an RFC process be needed for this change? If so, I would be willing to draft up a proposal.

[1] https://ghc.haskell.org/trac/ghc/ticket/10196