simple merging of Nat lists.
simple merging of Nat lists.

There is no duplicate prevention, i.e. 

prompt> mergeNL [0v, 1v, 4v]nl [1v]nl

(Just [0v,1v,1v,4v]nl) :: Maybe (NatList [0t,1t,1t,4t]i)

instead of Nothing :-(

cartazio/omega,minad/omega