Merge from /branches/features/STL_Extension-better_cpp0x_get-lrineau

STL_Extension/doc_tex/STL_Extension_ref/tuple.tex

@@ -33,7 +33,8 @@ is taken from Boost.
 
 Some free functions part of the standard interface of \ccc{tuple} are also
 brought in namespace \ccc{CGAL::cpp0x} with using declarations, these are \ccc{make_tuple},
-\ccc{get}, \ccc{tie}. 
+\ccc{get}, \ccc{tie}. Like in C++0x, the \ccc{get} function template is
+specialized so that it can take \ccc{std::pair} as argument.
 Two standard helper classes are also provided for convenience (\ccc{tuple_size} and \ccc{tuple_element}).
 
 \end{ccRefClass}

STL_Extension/include/CGAL/tuple.h

@@ -27,12 +27,15 @@
 
 #ifndef CGAL_CFG_NO_CPP0X_TUPLE
 #  include <tuple>
-#elif !defined CGAL_CFG_NO_TR1_TUPLE
-#  include <tr1/tuple>
-#else
-#  include <boost/tuple/tuple.hpp>
-#  include <boost/tuple/tuple_comparison.hpp>
 #endif
+#ifndef CGAL_CFG_NO_TR1_TUPLE
+#  include <tr1/tuple>
+#  include <tr1/utility>
+#endif
+
+#include <boost/tuple/tuple.hpp>
+#include <boost/tuple/tuple_comparison.hpp>
+#include <utility>
 
 namespace CGAL {
 
@@ -68,6 +71,47 @@ struct tuple_element: public boost::tuples::element<N,T>{};
   
 #endif
 
+
+#if defined(CGAL_CFG_NO_CPP0X_TUPLE) && defined(CGAL_CFG_NO_TR1_TUPLE)
+// If not TR1 or C++11 tuple, we need to add get<N>(std::pair).
+
+////////////////////////////////////////////////////////////
+//                                                        //
+// Allow CGAL::cpp0x::get<N>(std::pair), if N==0 or N==1. //
+//                                                        //
+// That is already in TR1 and C++11, but not in Boost.    //
+//                                                        //
+////////////////////////////////////////////////////////////
+template <std::size_t N, typename T1, typename T2>
+struct pair_get;
+
+template <typename T1, typename T2>
+struct pair_get<0, T1, T2> {
+  static T1& get(std::pair<T1, T2>& pair) { return pair.first; }
+  static const T1& get(const std::pair<T1, T2>& pair) { return pair.first; }
+}; // end specialization struct pair_get<0, T2, T2>
+
+template <typename T1, typename T2>
+struct pair_get<1, T1, T2> {
+  static T2& get(std::pair<T1, T2>& pair) { return pair.second; }
+  static const T2& get(const std::pair<T1, T2>& pair) { return pair.second; }
+}; // end specialization struct pair_get<0, T2, T2>
+
+template <std::size_t N, typename T1, typename T2>
+inline typename boost::tuples::element<N, boost::tuple<T1, T2> >::type&
+get(std::pair<T1, T2>& pair) {
+  return pair_get<N, T1, T2>::get(pair);
+}
+
+template <std::size_t N, typename T1, typename T2>
+inline const typename boost::tuples::element<N, boost::tuple<T1, T2> >::type&
+get(const std::pair<T1, T2>& pair) { 
+  return pair_get<N, T1, T2>::get(pair);
+}
+
+#endif // end if not C++11 tuple
+
+
 } // cpp0x
 
 #ifndef CGAL_CFG_NO_CPP0X_VARIADIC_TEMPLATES

STL_Extension/test/STL_Extension/test_stl_extension.cpp

@@ -8110,10 +8110,7 @@ void test_tuple(){
   
   T1 t1=CGAL::cpp0x::make_tuple(1,2);
   T1 t1_2=CGAL::cpp0x::make_tuple(1,2);
-  int i1=-1,i2=-1;
-  CGAL::cpp0x::tie(i1,i2)=t1;
-  CGAL_assertion( CGAL::cpp0x::get<0>(t1)==i1 );
-  CGAL_assertion( CGAL::cpp0x::get<1>(t1)==i2 );
+
   CGAL_assertion(t1==t1_2); // test the equality operator
 
   // T2 t2 = T2();
@@ -8122,6 +8119,22 @@ void test_tuple(){
   // Do not test equality between default initialized tuples, because
   // GNU/g++ version 4.1.2 does not default-initialize correctly
   // std::tr1::tuple.
+
+  // Test CGAL::cpp0x::tie
+  int i1=-1,i2=-1;
+  CGAL::cpp0x::tie(i1,i2)=t1;
+  CGAL_assertion( CGAL::cpp0x::get<0>(t1)==i1 );
+  CGAL_assertion( CGAL::cpp0x::get<1>(t1)==i2 );
+
+  // Test CGAL::cpp0x::get for a pair
+  double d = 1;
+  std::pair<int, double *> pair(-3, &d);
+  const std::pair<int, double *> const_pair(2, &d);
+
+  assert(CGAL::cpp0x::get<0>(pair) == -3);
+  assert(CGAL::cpp0x::get<1>(pair) == &d);
+  assert(CGAL::cpp0x::get<0>(const_pair) == 2);
+  assert(CGAL::cpp0x::get<1>(const_pair) == &d);
 }
 
 void test_prev_next()