ceph/src/boost/libs/variant/include/boost/variant/detail/variant_io.hpp

   1 //-----------------------------------------------------------------------------
   2 // boost variant/detail/variant_io.hpp header file
   3 // See http://www.boost.org for updates, documentation, and revision history.
   4 //-----------------------------------------------------------------------------
   5 //
   6 // Copyright (c) 2002-2003
   7 // Eric Friedman, Itay Maman
   8 //
   9 // Distributed under the Boost Software License, Version 1.0. (See
  10 // accompanying file LICENSE_1_0.txt or copy at
  11 // http://www.boost.org/LICENSE_1_0.txt)
  12
  13 #ifndef BOOST_VARIANT_DETAIL_VARIANT_IO_HPP
  14 #define BOOST_VARIANT_DETAIL_VARIANT_IO_HPP
  15
  16 #include <iosfwd> // for std::basic_ostream forward declare
  17
  18 #include <boost/variant/variant_fwd.hpp>
  19
  20 #include <boost/detail/templated_streams.hpp>
  21 #include <boost/variant/static_visitor.hpp>
  22
  23 namespace boost {
  24
  25 ///////////////////////////////////////////////////////////////////////////////
  26 // function template operator<<
  27 //
  28 // Outputs the content of the given variant to the given ostream.
  29 //
  30
  31 // forward declare (allows output of embedded variant< variant< ... >, ... >)
  32 template <
  33       BOOST_TEMPLATED_STREAM_ARGS(E,T)
  34     BOOST_TEMPLATED_STREAM_COMMA
  35       BOOST_VARIANT_ENUM_PARAMS(typename U)
  36     >
  37 inline BOOST_TEMPLATED_STREAM(ostream, E,T)& operator<<(
  38       BOOST_TEMPLATED_STREAM(ostream, E,T)& out
  39     , const variant< BOOST_VARIANT_ENUM_PARAMS(U) >& rhs
  40     );
  41
  42 namespace detail { namespace variant {
  43
  44 template <typename OStream>
  45 class printer
  46     : public boost::static_visitor<>
  47 {
  48 private: // representation
  49
  50     OStream& out_;
  51
  52 public: // structors
  53
  54     explicit printer(OStream& out)
  55         : out_( out )
  56     {
  57     }
  58
  59 public: // visitor interface
  60
  61     template <typename T>
  62     void operator()(const T& operand) const
  63     {
  64         out_ << operand;
  65     }
  66
  67 private:
  68     printer& operator=(const printer&);
  69
  70 };
  71
  72 }} // namespace detail::variant
  73
  74 template <
  75       BOOST_TEMPLATED_STREAM_ARGS(E,T)
  76     BOOST_TEMPLATED_STREAM_COMMA
  77       BOOST_VARIANT_ENUM_PARAMS(typename U)
  78     >
  79 inline BOOST_TEMPLATED_STREAM(ostream, E,T)& operator<<(
  80       BOOST_TEMPLATED_STREAM(ostream, E,T)& out
  81     , const variant< BOOST_VARIANT_ENUM_PARAMS(U) >& rhs
  82     )
  83 {
  84     detail::variant::printer<
  85           BOOST_TEMPLATED_STREAM(ostream, E,T)
  86         > visitor(out);
  87
  88     rhs.apply_visitor(visitor);
  89
  90     return out;
  91 }
  92
  93 } // namespace boost
  94
  95 #endif // BOOST_VARIANT_DETAIL_VARIANT_IO_HPP