ceph/src/boost/boost/fusion/support/unused.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3     Copyright (c) 2018 Kohei Takahashi
   4
   5     Distributed under the Boost Software License, Version 1.0. (See accompanying
   6     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7 ==============================================================================*/
   8 #if !defined(BOOST_FUSION_SUPPORT_UNUSED_20070305_1038)
   9 #define BOOST_FUSION_SUPPORT_UNUSED_20070305_1038
  10
  11 #include <boost/fusion/support/config.hpp>
  12 #include <iosfwd>
  13
  14 #if defined(BOOST_MSVC)
  15 # pragma warning(push)
  16 # pragma warning(disable: 4522) // multiple assignment operators specified warning
  17 #endif
  18
  19 #define BOOST_FUSION_UNUSED_HAS_IO
  20
  21 namespace boost { namespace fusion
  22 {
  23     struct unused_type
  24     {
  25         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  26         BOOST_DEFAULTED_FUNCTION(
  27         unused_type() BOOST_FUSION_NOEXCEPT_ON_DEFAULTED,
  28         {
  29         })
  30
  31         template <typename T>
  32         BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  33         unused_type(T const&) BOOST_NOEXCEPT
  34         {
  35         }
  36     };
  37
  38     BOOST_CONSTEXPR_OR_CONST unused_type unused = unused_type();
  39
  40     namespace detail
  41     {
  42         struct unused_only
  43         {
  44             BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  45             unused_only(unused_type const&) BOOST_NOEXCEPT {}
  46         };
  47     }
  48
  49     BOOST_CONSTEXPR
  50     inline std::ostream& operator<<(std::ostream& out, detail::unused_only const&) BOOST_NOEXCEPT
  51     {
  52         return out;
  53     }
  54
  55     BOOST_CONSTEXPR
  56     inline std::istream& operator>>(std::istream& in, unused_type&) BOOST_NOEXCEPT
  57     {
  58         return in;
  59     }
  60 }}
  61
  62 #if defined(BOOST_MSVC)
  63 # pragma warning(pop)
  64 #endif
  65
  66 #endif