Hello all,
It's come to my attention that there is a tiny lurking potential hole in
GHC's type safety around type families in the presence of
UndecidableInstances. Consider the following:
> type family F a b
> type instance F x x = Int
> type instance F [x] x = Bool
>
> type family G
(Sorry for the re-send - got the wrong subject line last time.)
Hello all,
It's come to my attention that there is a tiny lurking potential hole in
GHC's type safety around type families in the presence of
UndecidableInstances. Consider the following:
> type family F a b
> type instanc
In writing GHC plugins, how can I (a) add a module import (preferably
qualified) and (b) make vars/ids for names imported from the newly imported
module (to insert in the transformed Core code)?
If it's not possible to do what I want, I'd be willing to require an
explicit import (say "import quali
