Proof ptc_chk_typ _ _ v6_algorithms.

(* Specifications: *)
Lemma add_type :
forall (e : env_v6) (t : trm_v6), wf_v6 e -> decl_dec _ v6_pts e (Ax _ t).
Lemma add_type :
forall (e : env_v6) (t : trm_v6), wf_v6 e -> decl_dec _ v6_pts e (Ax _ t).