Using Hugs1.3c with p1, the system crashes typechecking the
following program.
I have also tried with Hugs13c without patch and it didn't work
If I comment the last definition it works
I have tried with Gofer and it works
>module HasParser where
>
>type Parser a = [a]
>
>data Fix f = In (f (Fix f))
>
>data N x = Num Int
> | Add x x
>
>type FN = Fix N
>
>class HasParser t where
> parser::Parser t
>
>instance (HasParser x) => HasParser (N x) where
> parser = [Num 3]
>
>instance HasParser (f (Fix f)) => HasParser (Fix f) where
> parser = map In parser
>
>
If I comment next definition, it works...
>parserFN::Parser FN
>parserFN = parser
