Register JMeq_congr as core.JMeq.congr.
(** [JMeq] is equivalent to [eq_dep Type (fun X => X)] *)

(* Specifications: *)
Lemma JMeq_eq_dep_id :
forall (A B:Type) (x:A) (y:B), JMeq x y -> eq_dep Type (fun X => X) A x B y.
Lemma eq_dep_id_JMeq :
forall (A B:Type) (x:A) (y:B), eq_dep Type (fun X => X) A x B y -> JMeq x y.