blob: 244eb92c59734a7bf393a1eff58027812d56aaae (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
(************************************************************************)
(* v * The Coq Proof Assistant / The Coq Development Team *)
(* <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 *)
(************************************************************************)
(* Evgeny Makarov, INRIA, 2007 *)
(************************************************************************)
(*i $Id$ i*)
Require Export Decidable.
Require Export ZAxioms.
Require Import NZProperties.
Module ZBasePropFunct (Import Z : ZAxiomsSig').
Include NZPropFunct Z.
(* Theorems that are true for integers but not for natural numbers *)
Theorem pred_inj : forall n m, P n == P m -> n == m.
Proof.
intros n m H. apply succ_wd in H. now do 2 rewrite succ_pred in H.
Qed.
Theorem pred_inj_wd : forall n1 n2, P n1 == P n2 <-> n1 == n2.
Proof.
intros n1 n2; split; [apply pred_inj | apply pred_wd].
Qed.
End ZBasePropFunct.
|