Scheme context_ind2 := Minimality for context Sort Prop
  with contextlist_ind2 := Minimality for contextlist Sort Prop.Combined Scheme context_contextlist_ind from context_ind2, contextlist_ind2.

Lemma safe_inv: forall k C f a K m, safe (ExprState f (C a) K e m) -> context k RV C -> match a with | Eloc _ _ _ => True | Eval _ _ => True | _ => invert_expr_prop a m end.