Ticket #2793: function_type_named_parameter.cpp

// Copyright Frank Mori Hess 2009.
// 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)

#include <boost/mpl/assert.hpp>
#include <boost/parameter.hpp>
#include <boost/type_traits/is_same.hpp>

namespace parameter = boost::parameter;

namespace test
{
  namespace keywords
  {
    BOOST_PARAMETER_TEMPLATE_KEYWORD(function_type)
  } // namespace keywords

  template <typename A0>
  class X
  {
    typedef parameter::parameters<
        parameter::required<keywords::tag::function_type>
      > parameter_spec;

  public:
    // ArgumentPack
    typedef typename
      parameter_spec::bind<A0>::type
      args;

    typedef typename parameter::binding<args, keywords::tag::function_type>::type
      type;
  };

  template <typename T>
  class Y
  {
  public:
    typedef T type;
  };
  BOOST_MPL_ASSERT((boost::is_same<X<keywords::function_type<void ()> >::type, Y<void ()>::type>));
} // namespace test