From a7ccc80f18d7aa239bb17ab2490aba25453fd409 Mon Sep 17 00:00:00 2001
From: Marc Glisse <marc.glisse@inria.fr>
Date: Sun, 17 May 2020 11:42:10 +0200
Subject: [PATCH] comparisons for MP_Float

---
 Number_types/include/CGAL/MP_Float.h | 47 +++++++++++++---------------
 1 file changed, 22 insertions(+), 25 deletions(-)

diff --git a/Number_types/include/CGAL/MP_Float.h b/Number_types/include/CGAL/MP_Float.h
index 56e22b7e39b..b0a161837c1 100644
--- a/Number_types/include/CGAL/MP_Float.h
+++ b/Number_types/include/CGAL/MP_Float.h
@@ -27,6 +27,7 @@
 #include <iostream>
 #include <vector>
 #include <algorithm>
+#include <boost/operators.hpp>
 
 // MP_Float : multiprecision scaled integers.
 
@@ -106,7 +107,13 @@ MP_Float operator*(const MP_Float &a, const MP_Float &b);
 MP_Float operator%(const MP_Float &a, const MP_Float &b);
 
 
-class MP_Float
+class MP_Float : boost::totally_ordered1<MP_Float
+#ifdef _MSC_VER
+                 , boost::equality_comparable2<MP_Float, int
+                 , boost::equality_comparable2<MP_Float, double
+                 > >
+#endif
+                 >
 {
 public:
   typedef short          limb;
@@ -223,6 +230,20 @@ public:
   MP_Float& operator*=(const MP_Float &a) { return *this = *this * a; }
   MP_Float& operator%=(const MP_Float &a) { return *this = *this % a; }
 
+  friend bool operator<(const MP_Float &a, const MP_Float &b)
+  { return INTERN_MP_FLOAT::compare(a, b) == SMALLER; }
+
+  friend bool operator==(const MP_Float &a, const MP_Float &b)
+  { return (a.v == b.v) && (a.v.empty() || (a.exp == b.exp)); }
+
+#ifdef _MSC_VER
+  // Needed because without /permissive-, it makes hidden friends visible (operator== from Quotient)
+  friend bool operator==(const MP_Float &a, int b)
+  { return a == MP_Float(b); }
+  friend bool operator==(const MP_Float &a, double b)
+  { return a == MP_Float(b); }
+#endif
+
   exponent_type max_exp() const
   {
     return exponent_type(v.size()) + exp;
@@ -365,30 +386,6 @@ inline
 void swap(MP_Float &m, MP_Float &n)
 { m.swap(n); }
 
-inline
-bool operator<(const MP_Float &a, const MP_Float &b)
-{ return INTERN_MP_FLOAT::compare(a, b) == SMALLER; }
-
-inline
-bool operator>(const MP_Float &a, const MP_Float &b)
-{ return b < a; }
-
-inline
-bool operator>=(const MP_Float &a, const MP_Float &b)
-{ return ! (a < b); }
-
-inline
-bool operator<=(const MP_Float &a, const MP_Float &b)
-{ return ! (a > b); }
-
-inline
-bool operator==(const MP_Float &a, const MP_Float &b)
-{ return (a.v == b.v) && (a.v.empty() || (a.exp == b.exp)); }
-
-inline
-bool operator!=(const MP_Float &a, const MP_Float &b)
-{ return ! (a == b); }
-
 MP_Float
 approximate_sqrt(const MP_Float &d);