That sounds like a bug/oversight! Is that not fixed in 9.2?
On Mon, Apr 5, 2021 at 11:08 PM David Feuer wrote:
> `Char` is defined in user code. What you really can't define are Char# and
> TYPE, and you can't modify `RuntimeRep`. Speaking of `Char#`, I see that in
> 9.0, at least, it has kind
> On Apr 6, 2021, at 7:44 AM, Anthony Clayden
> wrote:
>
> > But why does this matter?
>
> Because I want the semantics of that equality constraint, without switching
> on any of these, which I don't otherwise use:
>
> GADTs
> TypeFamilies
> TypeOperators
>
> And if that means I can't use
> But why does this matter?
Because I want the semantics of that equality constraint, without switching
on any of these, which I don't otherwise use:
GADTs
TypeFamilies
TypeOperators
And if that means I can't use infix `~` in my constraints, I'll put up with
that. (I'd user-define a
`Char` is defined in user code. What you really can't define are Char# and
TYPE, and you can't modify `RuntimeRep`. Speaking of `Char#`, I see that in
9.0, at least, it has kind TYPE 'WordRep. Why is that not Word32Rep?
On Mon, Apr 5, 2021, 10:50 PM Richard Eisenberg wrote:
>
>
> On Apr 1,
> On Apr 1, 2021, at 8:12 PM, Anthony Clayden
> wrote:
>
> Can I user-define a conventional type-class that behaves more like `(~)`?
I don't think so.
But why does this matter? I can't define `Char` in user code, but it's exported
from the Prelude and requires no extensions. While I can
Type equality `(~)` is a fine constraint. It's mildly annoying I need
either `-XGADTs` or `-XTypeFamilies` to use it -- because I don't otherwise
need those extensions. OTOH it's not H2010 so it needs to be switched on
somehow.
I see the Committee is discussing what to do. It's to be enabled by
