ceph/src/boost/libs/tr1/include/boost/tr1/utility.hpp

   1 //  (C) Copyright John Maddock 2005.
   2 //  Use, modification and distribution are subject to the
   3 //  Boost Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_TR1_UTILITY_HPP_INCLUDED
   7 #  define BOOST_TR1_UTILITY_HPP_INCLUDED
   8 #  include <boost/tr1/detail/config.hpp>
   9
  10 #ifdef BOOST_HAS_TR1_UTILITY
  11
  12 #  if defined(BOOST_HAS_INCLUDE_NEXT) && !defined(BOOST_TR1_DISABLE_INCLUDE_NEXT)
  13 #     include_next BOOST_TR1_HEADER(utility)
  14 #  else
  15 #     include <boost/tr1/detail/config_all.hpp>
  16 #     include BOOST_TR1_STD_HEADER(BOOST_TR1_PATH(utility))
  17 #  endif
  18
  19 #else
  20
  21 #if defined(BOOST_TR1_USE_OLD_TUPLE)
  22
  23 #include <boost/type_traits/integral_constant.hpp>
  24 #include <boost/type_traits/add_const.hpp>
  25 #include <boost/type_traits/add_reference.hpp>
  26 #include <boost/mpl/if.hpp>
  27
  28
  29 namespace std{ namespace tr1{
  30
  31 template <class T> struct tuple_size; // forward declaration
  32 template < int I, class T> struct tuple_element; // forward declaration
  33
  34 template <class T1, class T2>
  35 struct tuple_size< ::std::pair<T1, T2> >
  36    : public ::boost::integral_constant< ::std::size_t, 2>
  37 {
  38 };
  39
  40 template <class T1, class T2>
  41 struct tuple_element<0, ::std::pair<T1, T2> >
  42 {
  43    typedef typename std::pair<T1, T2>::first_type type;
  44 };
  45
  46 template <class T1, class T2>
  47 struct tuple_element<1, std::pair<T1, T2> >
  48 {
  49    typedef typename std::pair<T1, T2>::second_type type;
  50 };
  51
  52 namespace tuple_detail{
  53    template <int I, class T1, class T2>
  54    struct tuple_get_result
  55    {
  56       typedef typename boost::mpl::if_c<I==0, T1, T2>::type t1;
  57       typedef typename boost::add_reference<t1>::type type;
  58    };
  59    template <int I, class T1, class T2>
  60    struct const_tuple_get_result
  61    {
  62       typedef typename boost::mpl::if_c<I==0, T1, T2>::type t1;
  63 # if BOOST_WORKAROUND( __BORLANDC__, BOOST_TESTED_AT( 0x582))
  64       // I have absolutely no idea why add_const is not working here for Borland!
  65       // It passes all other free-standing tests, some strange interaction going on
  66       typedef typename boost::add_reference< const t1 >::type type;
  67 # else
  68       typedef typename boost::add_const<t1>::type t2;
  69       typedef typename boost::add_reference<t2>::type type;
  70 # endif
  71    };
  72
  73 template<int I, class T1, class T2>
  74 inline typename tuple_detail::tuple_get_result<I,T1,T2>::type get(std::pair<T1, T2>& p, const ::boost::true_type&)
  75 {
  76    return p.first;
  77 }
  78
  79 template<int I, class T1, class T2>
  80 inline typename tuple_detail::const_tuple_get_result<I,T1,T2>::type get(const std::pair<T1, T2>& p, const ::boost::true_type&)
  81 {
  82    return p.first;
  83 }
  84
  85 template<int I, class T1, class T2>
  86 inline typename tuple_detail::tuple_get_result<I,T1,T2>::type get(std::pair<T1, T2>& p, const ::boost::false_type&)
  87 {
  88    return p.second;
  89 }
  90
  91 template<int I, class T1, class T2>
  92 inline typename tuple_detail::const_tuple_get_result<I,T1,T2>::type get(const std::pair<T1, T2>& p, const ::boost::false_type&)
  93 {
  94    return p.second;
  95 }
  96
  97 }
  98
  99 template<int I, class T1, class T2>
 100 inline typename tuple_detail::tuple_get_result<I,T1,T2>::type get(std::pair<T1, T2>& p)
 101 {
 102    return tuple_detail::get<I>(p, boost::integral_constant<bool, I==0>());
 103 }
 104
 105 template<int I, class T1, class T2>
 106 inline typename tuple_detail::const_tuple_get_result<I,T1,T2>::type get(const std::pair<T1, T2>& p)
 107 {
 108    return tuple_detail::get<I>(p, boost::integral_constant<bool, I==0>());
 109 }
 110
 111 } } // namespaces
 112
 113 #else
 114
 115 #include <boost/tr1/tuple.hpp>
 116
 117 #endif
 118
 119 #endif
 120
 121 #endif