Fixpoint Map_of_alist (l:alist) : Map A :=
    match l with
    | nil => M0 A
    | (a, y) :: l' => MapPut A (Map_of_alist l') a y
    end.

Lemma alist_semantics_disjoint_comm : forall l l':alist, eqmap A (MapDomRestrTo A A (Map_of_alist l) (Map_of_alist l')) (M0 A) -> eqm A (alist_semantics (aapp l l')) (alist_semantics (aapp l' l)).