(* Ramification Premises for Nested Load/Store Rule *)

Lemma RP_field: forall t nf u v p,
legal_nested_field t nf ->
legal_type t ->
data_at t u p |-- field_at t nf (proj_reptype t nf u) p *
(field_at t nf v p -* data_at t (upd_reptype t nf u v) p).