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authorGravatar letouzey <letouzey@85f007b7-540e-0410-9357-904b9bb8a0f7>2011-05-05 15:12:09 +0000
committerGravatar letouzey <letouzey@85f007b7-540e-0410-9357-904b9bb8a0f7>2011-05-05 15:12:09 +0000
commitf61a557fbbdb89a4c24a8050a67252c3ecda6ea7 (patch)
tree3808b3b5a9fc4a380307545e10845882300ef6aa /theories/Numbers/BinNums.v
parent81d7335ba1a07a7a30e206ae3ffc4412f3a54f46 (diff)
Definitions of positive, N, Z moved in Numbers/BinNums.v
In the coming reorganisation, the name Z in BinInt will be a module containing all code and properties about binary integers. The inductive type Z hence cannot be at the same location. Same for N and positive. Apart for this naming constraint, it also have advantages : presenting the three types at once is clearer, and we will be able to refer to N in BinPos (for instance for output type of a predecessor function on positive). git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@14097 85f007b7-540e-0410-9357-904b9bb8a0f7
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+(************************************************************************)
+(* 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 *)
+(************************************************************************)
+
+(** * Binary Numerical Datatypes *)
+
+Set Implicit Arguments.
+(* For compatibility, we will not use generic equality functions *)
+Local Unset Boolean Equality Schemes.
+
+Declare ML Module "z_syntax_plugin".
+
+(** [positive] is a datatype representing the strictly positive integers
+ in a binary way. Starting from 1 (represented by [xH]), one can
+ add a new least significant digit via [xO] (digit 0) or [xI] (digit 1).
+ Numbers in [positive] can also be denoted using a decimal notation;
+ e.g. [6%positive] abbreviates [xO (xI xH)] *)
+
+Inductive positive : Set :=
+ | xI : positive -> positive
+ | xO : positive -> positive
+ | xH : positive.
+
+Delimit Scope positive_scope with positive.
+Bind Scope positive_scope with positive.
+Arguments Scope xO [positive_scope].
+Arguments Scope xI [positive_scope].
+
+(** [N] is a datatype representing natural numbers in a binary way,
+ by extending the [positive] datatype with a zero.
+ Numbers in [N] can also be denoted using a decimal notation;
+ e.g. [6%N] abbreviates [Npos (xO (xI xH))] *)
+
+Inductive N : Set :=
+ | N0 : N
+ | Npos : positive -> N.
+
+Delimit Scope N_scope with N.
+Bind Scope N_scope with N.
+Arguments Scope Npos [positive_scope].
+
+(** [Z] is a datatype representing the integers in a binary way.
+ An integer is either zero or a strictly positive number
+ (coded as a [positive]) or a strictly negative number
+ (whose opposite is stored as a [positive] value).
+ Numbers in [Z] can also be denoted using a decimal notation;
+ e.g. [(-6)%Z] abbreviates [Zneg (xO (xI xH))] *)
+
+Inductive Z : Set :=
+ | Z0 : Z
+ | Zpos : positive -> Z
+ | Zneg : positive -> Z.
+
+Delimit Scope Z_scope with Z.
+Bind Scope Z_scope with Z.
+Arguments Scope Zpos [positive_scope].
+Arguments Scope Zneg [positive_scope].