Section MapC.
Variables A B C : Type.

Lemma MapMerge_RestrTo_l_c :
forall m m' m'':Map A,
mapcanon A m ->
mapcanon A m'' ->
MapMerge A (MapDomRestrTo A A m m') m'' =
MapDomRestrTo A A (MapMerge A m m'') (MapMerge A m' m'').