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+(************************************************************************)
+(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
+(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *)
+(*   \VV/  **************************************************************)
+(*    //   *      This file is distributed under the terms of the       *)
+(*         *       GNU Lesser General Public License Version 2.1        *)
+(************************************************************************)
+
+(* $Id: ZArithRing.v,v 1.1.2.1 2004/07/16 19:30:19 herbelin Exp $ *)
+
+(* Instantiation of the Ring tactic for the binary integers of ZArith *)
+
+Require Export ArithRing.
+Require Export ZArith_base.
+Require Eqdep_dec.
+
+Definition Zeq := [x,y:Z]
+  Cases `x ?= y ` of
+    EGAL => true
+  | _ => false
+  end.
+
+Lemma Zeq_prop : (x,y:Z)(Is_true (Zeq x y)) -> x==y.
+  Intros x y H; Unfold Zeq in H.
+  Apply Zcompare_EGAL_eq.
+  NewDestruct (Zcompare x y); [Reflexivity | Contradiction | Contradiction ].
+Save.
+
+Definition ZTheory : (Ring_Theory Zplus Zmult `1` `0` Zopp Zeq).
+  Split; Intros; Apply eq2eqT; EAuto with zarith.
+  Apply eqT2eq; Apply Zeq_prop; Assumption.
+Save.
+
+(* NatConstants and NatTheory are defined in Ring_theory.v *)
+Add Ring Z Zplus Zmult `1` `0` Zopp Zeq ZTheory [POS NEG ZERO xO xI xH].