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.

Theorem JMeq_eq : forall (A:Type) (x y:A), JMeq x y -> x = y.