Mon Jul 20 02:52:42 EDT 2015


There's a point to make about:

   data Op i o = forall s. (Comp s i o) => (s, (s,i)->(s,o))

Without the Comp constraint -- which would implement some kind of
access to do compilation of the internals -- this can be flattened to
[i] -> [o] or some other collection K i -> K o, without knowing
anything about s.

But that's the only thing that can be done!