Lemma MapFold_Put_disjoint_1 : forall (p:positive) (f:ad -> A -> M) (pf:ad -> ad) (a1 a2:ad) (y1 y2:A), Nxor a1 a2 = Npos p -> MapFold1 A M neutral op f pf (MapPut1 A a1 y1 a2 y2 p) = op (f (pf a1) y1) (f (pf a2) y2).