Inductive JMeq (A:Type) (x:A) : forall B:Type, B -> Prop :=
    JMeq_refl : JMeq x x.Inductive JMeq (A:Type) (x:A) : forall B:Type, B -> Prop :=
    JMeq_refl : JMeq x x.Definition JMeq_hom {A : Type} (x y : A) := JMeq x y.

Lemma JMeq_rect_r : forall (A:Type) (x:A) (P:A -> Type), P x -> forall y, JMeq y x -> P y.