proposition: Lemma last_holder'_no_out_extend : forall tr h c n, last_holder' h tr = Some n -> last_holder' h (tr ++ [(c, inr [])]) = Some n.
proof: Proof. Proof using. induction tr; intros; simpl in *; repeat break_match; subst; intuition. Qed.
imports: Verdi(Verdi HandlerMonad) StructTact(Fin) Verdi(StatePacketPacketDecomposition)