Sun Aug 2 16:16:27 EDT 2015

commutation again

This time   v (a, b)  <-> (v a, v b)

Essentially, I'd like to fold over a vector of tuples.

Maide a pair/unpair addition to Rep

Ming with Pair then boils down to:

    No instances for (TypeOf (v0 (a0, b0)), TypeOf (a0, b0))

Which is meaningless.  TypeOf needs to be removed as constraint.
Or it needs to commute with (,) ?