fact: Axiom disjoint_one_2 : forall A B (x : atom) (a : A) (F : list (atom*B)), ~ In x (dom F) -> disjoint (x ~ a) F.
imports: Coq.FSets.FSets Coq.Lists.List Coq.Logic.Decidable Metalib.CoqFSetDecide Metalib.CoqListFacts Metalib.AssocList Metalib.MetatheoryAtom Metalib.LibTactics