From 3fd6c79ae8d1b2c6e78763c0758a5bb9f95e34b3 Mon Sep 17 00:00:00 2001 From: Claudio Sacerdoti Coen Date: Thu, 21 Jul 2005 14:34:17 +0000 Subject: [PATCH] S_pred moved from Z/times.ma to nat/orders.ma --- helm/matita/library/Z/times.ma | 5 ----- helm/matita/library/nat/orders.ma | 10 +++++++--- 2 files changed, 7 insertions(+), 8 deletions(-) diff --git a/helm/matita/library/Z/times.ma b/helm/matita/library/Z/times.ma index 6e7a59d16..bb5ed67c5 100644 --- a/helm/matita/library/Z/times.ma +++ b/helm/matita/library/Z/times.ma @@ -38,11 +38,6 @@ simplify.reflexivity. simplify.reflexivity. qed. -(* da spostare in nat/order *) -theorem S_pred: \forall n:nat.lt O n \to eq nat n (S (pred n)). -intro.elim n.apply False_ind.exact not_le_Sn_O O H. -apply eq_f.apply pred_Sn. -qed. (* theorem symmetric_Ztimes : symmetric Z Ztimes. diff --git a/helm/matita/library/nat/orders.ma b/helm/matita/library/nat/orders.ma index d4979231d..34cd6f6a3 100644 --- a/helm/matita/library/nat/orders.ma +++ b/helm/matita/library/nat/orders.ma @@ -83,6 +83,12 @@ apply H.assumption. apply le_S_S_to_le.assumption. qed. +(* ??? this needs not le *) +theorem S_pred: \forall n:nat.lt O n \to eq nat n (S (pred n)). +intro.elim n.apply False_ind.exact not_le_Sn_O O H. +apply eq_f.apply pred_Sn. +qed. + (* le vs. lt *) theorem lt_to_le : \forall n,m:nat. lt n m \to le n m. simplify.intros.elim H. @@ -150,6 +156,4 @@ intros.simplify.right.exact not_le_Sn_O n1. intros 2.simplify.intro.elim H. left.apply le_S_S.assumption. right.intro.apply H1.apply le_S_S_to_le.assumption. -qed. - - +qed. \ No newline at end of file -- 2.39.2