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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 *)
+(************************************************************************)
+(* Benjamin Gregoire, Laurent Thery, INRIA, 2007 *)
+(************************************************************************)
+
+(* $Id: QMake_base.v 10964 2008-05-22 11:08:13Z letouzey $ *)
+
+(** * An implementation of rational numbers based on big integers *)
+
+Require Export BigN.
+Require Export BigZ.
+
+(* Basic type for Q: a Z or a pair of a Z and an N *)
+
+Inductive q_type :=
+ | Qz : BigZ.t -> q_type
+ | Qq : BigZ.t -> BigN.t -> q_type.
+
+Definition print_type x :=
+ match x with
+ | Qz _ => Z
+ | _ => (Z*Z)%type
+ end.
+
+Definition print x :=
+ match x return print_type x with
+ | Qz zx => BigZ.to_Z zx
+ | Qq nx dx => (BigZ.to_Z nx, BigN.to_Z dx)
+ end.