boost/parameter/aux_/void.hpp

// Copyright Daniel Wallin, David Abrahams 2005. Use, modification and
// distribution is subject to 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_PARAMETER_VOID_050329_HPP
#define BOOST_PARAMETER_VOID_050329_HPP

namespace boost { namespace parameter { 

// A placemarker for "no argument passed."
// MAINTAINER NOTE: Do not make this into a metafunction
struct void_ {}; 

namespace aux 
{

  inline void_& void_reference()
  {
      static void_ instance;
      return instance;
  }

} // namespace aux

}} // namespace boost::parameter

#endif // BOOST_PARAMETER_VOID_050329_HPP

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boost/parameter/aux_/void.hpp