proposition: Lemma binds_app_uniq_iff : uniq (E ++ F) -> (binds x a (E ++ F) <-> (binds x a E /\ ~ In x (dom F)) \/ (binds x a F /\ ~ In x (dom E))).
proof: Proof. clear. intuition auto using binds_app_uniq_1, binds_app_2, binds_app_3. Qed.
imports: Coq.FSets.FSets Coq.Lists.List Coq.Logic.Decidable Coq.Strings.String String Metalib.CoqFSetDecide Metalib.CoqListFacts Metalib.LibTactics Metalib.CoqFSetInterface Coq.Classes.Equivalence Coq.Classes.EquivDec Metalib.CoqEqDec