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-rw-r--r--theories/Arith/Plus.v31
1 files changed, 8 insertions, 23 deletions
diff --git a/theories/Arith/Plus.v b/theories/Arith/Plus.v
index 12f12300..02975d8f 100644
--- a/theories/Arith/Plus.v
+++ b/theories/Arith/Plus.v
@@ -1,13 +1,11 @@
-(************************************************************************)
+ (************************************************************************)
(* v * The Coq Proof Assistant / The Coq Development Team *)
-(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2011 *)
+(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2010 *)
(* \VV/ **************************************************************)
(* // * This file is distributed under the terms of the *)
(* * GNU Lesser General Public License Version 2.1 *)
(************************************************************************)
-(*i $Id: Plus.v 14641 2011-11-06 11:59:10Z herbelin $ i*)
-
(** Properties of addition. [add] is defined in [Init/Peano.v] as:
<<
Fixpoint plus (n m:nat) : nat :=
@@ -26,17 +24,10 @@ Open Local Scope nat_scope.
Implicit Types m n p q : nat.
-(** * Zero is neutral *)
-
-Lemma plus_0_l : forall n, 0 + n = n.
-Proof.
- reflexivity.
-Qed.
-
-Lemma plus_0_r : forall n, n + 0 = n.
-Proof.
- intro; symmetry in |- *; apply plus_n_O.
-Qed.
+(** * Zero is neutral
+Deprecated : Already in Init/Peano.v *)
+Notation plus_0_l := plus_O_n (only parsing).
+Definition plus_0_r n := eq_sym (plus_n_O n).
(** * Commutativity *)
@@ -49,14 +40,8 @@ Hint Immediate plus_comm: arith v62.
(** * Associativity *)
-Lemma plus_Snm_nSm : forall n m, S n + m = n + S m.
-Proof.
- intros.
- simpl in |- *.
- rewrite (plus_comm n m).
- rewrite (plus_comm n (S m)).
- trivial with arith.
-Qed.
+Definition plus_Snm_nSm : forall n m, S n + m = n + S m:=
+ plus_n_Sm.
Lemma plus_assoc : forall n m p, n + (m + p) = n + m + p.
Proof.