End EVENTVAL.
(** Invariance under changes to the global environment *)
Section EVENTVAL_INV.
Variables ge1 ge2: Senv.t.
Hypothesis public_preserved:
forall id, Senv.public_symbol ge2 id = Senv.public_symbol ge1 id.

(* Specifications: *)
Lemma eventval_valid_preserved:
forall ev, eventval_valid ge1 ev -> eventval_valid ge2 ev.