Keith Battocchi wrote:
> data Nest a = Nil | Cons(a, (Nest (Pair a)))
> type Pair a = (a,a)
>
> pair f (a,b) = (f a, f b)
>
> efold :: forall n m b.
> (forall a. n a)
> -> (forall a . (m a, n (Pair a)) -> n a)
> -> (forall a. Pair (m a) -> m (Pair a))
> -> (forall l z. (l b -> m (z b))
On Fri, Apr 24, 2009 at 06:52:09PM +, Keith Battocchi wrote:
> I'm trying to write some code to do folds on nested datatypes as in
> http://web.comlab.ox.ac.uk/people/Jeremy.Gibbons/publications/efolds.pdf but
> running into trouble getting things to typecheck.
>
> Given the types
>
> data
I'm trying to write some code to do folds on nested datatypes as in
http://web.comlab.ox.ac.uk/people/Jeremy.Gibbons/publications/efolds.pdf but
running into trouble getting things to typecheck.
Given the types
data Nest a = Nil | Cons(a, (Nest (Pair a)))
type Pair a = (a,a)
and the following
