proposition: Lemma binds_In : forall x a (E : list (X.t*A)), binds x a E -> In x (dom E).
proof: Proof. clear. alist induction E as [ | y ? F ]; intros J; simpl_alist. analyze_binds J. analyze_binds J; subst; auto with set. 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