proposition: Lemma compat4_wcompat clo (CMP: compatible4 clo): wcompatible4 clo.
proof: Proof. econstructor. apply CMP. intros. apply CMP in PR. eapply gf_mon. apply PR. intros. apply gpaco4_clo, PR0. Qed.
imports: Program.Basics Paco(paco4 pacotac)