Section MapAxioms.
Variables A B C : Type.
Definition eqmap (m m':Map A) := eqm A (MapGet A m) (MapGet A m').

Lemma MapMerge_assoc :
forall m m' m'':Map A,
eqmap (MapMerge A (MapMerge A m m') m'')
(MapMerge A m (MapMerge A m' m'')).