Hi, ignore this mail. This is already shepherded by Richard. (I was thrown off by his “I'm happy with the new wording and would support this in a committee vote.” which sounded like something someone would say who is not in the position to propose acceptance :-))) Cheers, Joachim Am Freitag, dem 09.12.2022 um 20:07 +0100 schrieb Joachim Breitner:

Dear all,

Vlad has submitted a bug fix amendment to #448, to fix the wording around type variables in signatures within explicit type annotations:

https://github.com/ghc-proposals/ghc-proposals/pull/556/files

I’m shepherding that one myself.

The gist is that in

data Proxy a = P g :: Proxy (Nothing @(a, a)) -> () g (P @(Nothing :: Maybe (x, x))) = ()

the multiple occurrences of `a` are non-linear patterns and disallowed, but the multiple patterns of `x` are fine, because that’s how type variables in signatures in patterns happen to work. Vlad fixed the wording with regard to that in #448.

Simon and Richard already signaled support on the Github thread, which I recommend to follow. I don’t expect much further discussion around this and will happily merge after a week of silence (or after one or two additional confirmations).

Cheers, Joachim

-- Joachim Breitner mail@joachim-breitner.de http://www.joachim-breitner.de/