Definition extensible_jam: forall A (S': A -> Prop) S (P Q: A -> pred rmap),
      (forall (x: A), boxy extendM (P x)) ->
      (forall x, boxy extendM (Q x)) ->
      forall x, boxy extendM  (@jam _ _ _ _ _ _ S' S P Q x).Definition jam_vacuous:
  forall A JA PA agA AgeA B S S' P Q, (forall x:B, ~ S x) -> @jam A JA PA agA AgeA B S S' P Q = Q.

(* Specifications: *)
Lemma is_resource_pred_resource_stable: forall {p}, (exists q, is_resource_pred p q) -> resource_stable p.