proposition: Lemma plus_ge_compat : forall m n m' n', m >>= m' -> n >>= n' -> m + n >>= m' + n'.
proof: Proof. intros. destruct m; destruct n; destruct m'; destruct n'; simpl; trivial; arctic_ord. apply max_ge_compat; hyp. unfold Peano.ge. apply le_max_intro_l. hyp. unfold Peano.ge. apply le_max_intro_r. hyp. Qed.
imports: Coq(Morphisms) CoLoR(RelDec RelUtil SN RelExtras NatUtil LogicUtil ZUtil)