proposition: Lemma var_reverse_term : forall t, var (reverse_term t) = 0.
proof: Proof. intro t; pattern t; apply (term_ind_forall is_unary_sig); clear t; intros. refl. unfold reverse_term. rewrite string_of_term_fun1, rev'_cons, term_of_string_app. change (var (sub (@ATerm_of_String.sub_of_string SSig (f :: nil)) (reverse_term t)) = 0). rewrite var_sub. 2: apply is_unary_sig'. rewrite H. refl. Qed.
imports: CoLoR(Srs ATrs SReverse ATerm_of_String String_of_ATerm AUnary SN LogicUtil AMorphism EqUtil NatUtil ListUtil VecUtil)