Module BAF := BA_Facts BA.(* Now, we prove the axioms about relativization.
     Again, this mostly involves packing and unpacking
     the canonTree type and pushing around mkCanon.
   *)

    Definition rel (a x:t) : t.

Lemma rel_inj_r : forall a1 a2 x, x <> bot -> rel a1 x = rel a2 x -> a1 = a2.