ceph/src/boost/libs/core/include/boost/core/swap.hpp

   1 // Copyright (C) 2007, 2008 Steven Watanabe, Joseph Gauterin, Niels Dekker
   2 //
   3 // Distributed under the Boost Software License, Version 1.0. (See
   4 // accompanying file LICENSE_1_0.txt or copy at
   5 // http://www.boost.org/LICENSE_1_0.txt)
   6 // For more information, see http://www.boost.org
   7
   8
   9 #ifndef BOOST_CORE_SWAP_HPP
  10 #define BOOST_CORE_SWAP_HPP
  11
  12 // Note: the implementation of this utility contains various workarounds:
  13 // - swap_impl is put outside the boost namespace, to avoid infinite
  14 // recursion (causing stack overflow) when swapping objects of a primitive
  15 // type.
  16 // - swap_impl has a using-directive, rather than a using-declaration,
  17 // because some compilers (including MSVC 7.1, Borland 5.9.3, and
  18 // Intel 8.1) don't do argument-dependent lookup when it has a
  19 // using-declaration instead.
  20 // - boost::swap has two template arguments, instead of one, to
  21 // avoid ambiguity when swapping objects of a Boost type that does
  22 // not have its own boost::swap overload.
  23
  24 #include <utility> //for std::swap (C++11)
  25 #include <algorithm> //for std::swap (C++98)
  26 #include <cstddef> //for std::size_t
  27 #include <boost/config.hpp>
  28
  29 namespace boost_swap_impl
  30 {
  31   template<class T>
  32   BOOST_GPU_ENABLED
  33   void swap_impl(T& left, T& right)
  34   {
  35     using namespace std;//use std::swap if argument dependent lookup fails
  36     swap(left,right);
  37   }
  38
  39   template<class T, std::size_t N>
  40   BOOST_GPU_ENABLED
  41   void swap_impl(T (& left)[N], T (& right)[N])
  42   {
  43     for (std::size_t i = 0; i < N; ++i)
  44     {
  45       ::boost_swap_impl::swap_impl(left[i], right[i]);
  46     }
  47   }
  48 }
  49
  50 namespace boost
  51 {
  52   template<class T1, class T2>
  53   BOOST_GPU_ENABLED
  54   void swap(T1& left, T2& right)
  55   {
  56     ::boost_swap_impl::swap_impl(left, right);
  57   }
  58 }
  59
  60 #endif