proposition: Lemma lhs_args_eq : forall f n (ts : Tes n) r (h : rule (apps (Fun f) ts) r), lhs_args h = Vcast ts (lhs_nb_args_eq_sym h).
proof: Proof. intros f n ts r h. gen (lhs_ok h); intro e. symmetry in e. gen (eq_apps_fun_args e); intro i. rewrite i. apply Vcast_pi. Qed.
imports: Coq(Morphisms Basics Lia) CoLoR(LogicUtil RelUtil VecOrd VecUtil LAlpha)