Hint Extern 0 (RIntro _ (klr_pullw _ _ _) _ _) =>
eapply klr_pullw_rintro : typeclass_instances.

Lemma klr_pullw_relim {W1 W2 A B} (f: W1 -> W2) R w (x:A) (y:B) P Q:
RElim (R (f w)) x y P Q ->
RElim (klr_pullw f R w) x y P Q.