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/*=============================================================================
Copyright (c) 2001-2014 Joel de Guzman
Copyright (c) 2001-2011 Hartmut Kaiser
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)
==============================================================================*/
#if !defined(BOOST_SPIRIT_X3_UNUSED_APRIL_16_2006_0616PM)
#define BOOST_SPIRIT_X3_UNUSED_APRIL_16_2006_0616PM
#include <ostream>
#include <istream>
#include <boost/mpl/identity.hpp>
#if defined(BOOST_MSVC)
# pragma warning(push)
# pragma warning(disable: 4522) // multiple assignment operators specified warning
#endif
///////////////////////////////////////////////////////////////////////////////
namespace boost { namespace spirit { namespace x3
{
struct unused_type
{
unused_type()
{
}
template <typename T>
unused_type(T const&)
{
}
template <typename T>
unused_type const&
operator=(T const&) const
{
return *this;
}
template <typename T>
unused_type&
operator=(T const&)
{
return *this;
}
unused_type const&
operator=(unused_type const&) const
{
return *this;
}
unused_type&
operator=(unused_type const&)
{
return *this;
}
// unused_type can also masquerade as an empty context (see context.hpp)
template <typename ID>
unused_type get(ID) const
{
return {};
}
};
auto const unused = unused_type{};
inline std::ostream& operator<<(std::ostream& out, unused_type const&)
{
return out;
}
inline std::istream& operator>>(std::istream& in, unused_type&)
{
return in;
}
}}}
#if defined(BOOST_MSVC)
# pragma warning(pop)
#endif
#endif
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