fact: Axiom disjoint_one_r : forall A B (x : atom) (a : A) (E : list (atom*B)), disjoint E (x ~ a) <-> ~ In x (dom E).
imports: Coq.FSets.FSets Coq.Lists.List Coq.Logic.Decidable Metalib.CoqFSetDecide Metalib.CoqListFacts Metalib.AssocList Metalib.MetatheoryAtom Metalib.LibTactics