proposition: Lemma uniq_app_2 : uniq (E ++ F) -> uniq F.
proof: Proof. clear. intros J. alist induction E. auto. inversion J; subst. auto. 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