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

Lemma MapDelta_as_DomRestrBy :
forall m m':Map A,
eqmap (MapDelta A m m')
(MapDomRestrBy A A (MapMerge A m m') (MapDomRestrTo A A m m')).