boost/boost/exception/detail/is_output_streamable.hpp

   1 //Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc.
   2
   3 //Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef UUID_898984B4076411DD973EDFA055D89593
   7 #define UUID_898984B4076411DD973EDFA055D89593
   8 #if defined(__GNUC__) && !defined(BOOST_EXCEPTION_ENABLE_WARNINGS)
   9 #pragma GCC system_header
  10 #endif
  11 #if defined(_MSC_VER) && !defined(BOOST_EXCEPTION_ENABLE_WARNINGS)
  12 #pragma warning(push,1)
  13 #endif
  14
  15 #include <ostream>
  16
  17 namespace
  18 boost
  19     {
  20     namespace
  21     to_string_detail
  22         {
  23         struct
  24         partial_ordering_helper1
  25             {
  26             template <class CharT,class Traits>
  27             partial_ordering_helper1( std::basic_ostream<CharT,Traits> & );
  28             };
  29
  30         struct
  31         partial_ordering_helper2
  32             {
  33             template <class T>
  34             partial_ordering_helper2( T const & );
  35             };
  36
  37         char operator<<( partial_ordering_helper1, partial_ordering_helper2 );
  38
  39         template <class T,class CharT,class Traits>
  40         struct
  41         is_output_streamable_impl
  42             {
  43             static std::basic_ostream<CharT,Traits> & f();
  44             static T const & g();
  45             enum e { value=1!=(sizeof(f()<<g())) };
  46             };
  47         }
  48
  49     template <class T, class CharT=char, class Traits=std::char_traits<CharT> >
  50     struct
  51     is_output_streamable
  52         {
  53         enum e { value=to_string_detail::is_output_streamable_impl<T,CharT,Traits>::value };
  54         };
  55     }
  56
  57 #if defined(_MSC_VER) && !defined(BOOST_EXCEPTION_ENABLE_WARNINGS)
  58 #pragma warning(pop)
  59 #endif
  60 #endif