Definition identity_rmap' : R.rmap' := exist valid (fun _: AV.address => R.NO) AV.valid_empty.Definition identity_rmap (n:nat) : rmap := R.squash (n, identity_rmap').

Lemma YES_join_full: forall n P r2 r3, join (R.YES pfullshare n P) r2 r3 -> r2 = NO.