ext-boost/boost/variant/detail/variant_io.hpp
2017-03-12 21:30:15 -07:00

96 lines
2.3 KiB
C++

//-----------------------------------------------------------------------------
// boost variant/detail/variant_io.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2002-2003
// Eric Friedman, Itay Maman
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_VARIANT_DETAIL_VARIANT_IO_HPP
#define BOOST_VARIANT_DETAIL_VARIANT_IO_HPP
#include <iosfwd> // for std::basic_ostream forward declare
#include <boost/variant/variant_fwd.hpp>
#include <boost/detail/templated_streams.hpp>
#include <boost/variant/static_visitor.hpp>
namespace boost {
///////////////////////////////////////////////////////////////////////////////
// function template operator<<
//
// Outputs the content of the given variant to the given ostream.
//
// forward declare (allows output of embedded variant< variant< ... >, ... >)
template <
BOOST_TEMPLATED_STREAM_ARGS(E,T)
BOOST_TEMPLATED_STREAM_COMMA
BOOST_VARIANT_ENUM_PARAMS(typename U)
>
inline BOOST_TEMPLATED_STREAM(ostream, E,T)& operator<<(
BOOST_TEMPLATED_STREAM(ostream, E,T)& out
, const variant< BOOST_VARIANT_ENUM_PARAMS(U) >& rhs
);
namespace detail { namespace variant {
template <typename OStream>
class printer
: public boost::static_visitor<>
{
private: // representation
OStream& out_;
public: // structors
explicit printer(OStream& out)
: out_( out )
{
}
public: // visitor interface
template <typename T>
void operator()(const T& operand) const
{
out_ << operand;
}
private:
printer& operator=(const printer&);
};
}} // namespace detail::variant
template <
BOOST_TEMPLATED_STREAM_ARGS(E,T)
BOOST_TEMPLATED_STREAM_COMMA
BOOST_VARIANT_ENUM_PARAMS(typename U)
>
inline BOOST_TEMPLATED_STREAM(ostream, E,T)& operator<<(
BOOST_TEMPLATED_STREAM(ostream, E,T)& out
, const variant< BOOST_VARIANT_ENUM_PARAMS(U) >& rhs
)
{
detail::variant::printer<
BOOST_TEMPLATED_STREAM(ostream, E,T)
> visitor(out);
rhs.apply_visitor(visitor);
return out;
}
} // namespace boost
#endif // BOOST_VARIANT_DETAIL_VARIANT_IO_HPP