proposition: Lemma ZOOOPST_singleton_inl : forall A B C h i, @zero_or_one_outputs_per_step_trace A B C [(h, inl i)].
proof: Proof. Proof using. unfold zero_or_one_outputs_per_step_trace, zero_or_one_outputs_per_step. simpl. intuition. subst. discriminate. Qed.
imports: Verdi(Verdi HandlerMonad)