proposition: Lemma ren_compatible_par s s' delta: s ≫ s' -> ren delta s ≫ ren delta s'.
proof: Proof. induction 1 in delta |-*; cbn; auto; subst. econstructor; auto. now asimpl. Qed.
imports: Morphisms Setoid Undecidability.HOU(std.std) Undecidability.HOU.calculus(prelim terms semantics)