Set Implicit Arguments. Unset Elimination Schemes. Inductive JMeq (A:Type) (x:A) : forall B:Type, B -> Prop := JMeq_refl : JMeq x x. Set Elimination Schemes. Register JMeq as core.JMeq.type. Axiom JMeq_ind : forall (A:Type) (x:A) (P:A -> Prop), P x -> forall y, JMeq x y -> P y. Register JMeq_ind as core.JMeq.ind. Lemma JMeq_ind_r : forall (A:Type) (x:A) (P:A -> Prop), P x -> forall y, JMeq y x -> P y. Proof. intros. try rewrite H0. Abort.