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#ifndef NDNBOOST_MPL_IS_PLACEHOLDER_HPP_INCLUDED
#define NDNBOOST_MPL_IS_PLACEHOLDER_HPP_INCLUDED
// Copyright Aleksey Gurtovoy 2001-2004
//
// 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)
//
// See http://www.boost.org/libs/mpl for documentation.
// $Id: is_placeholder.hpp 49267 2008-10-11 06:19:02Z agurtovoy $
// $Date: 2008-10-10 23:19:02 -0700 (Fri, 10 Oct 2008) $
// $Revision: 49267 $
#include <ndnboost/mpl/arg_fwd.hpp>
#include <ndnboost/mpl/bool.hpp>
#include <ndnboost/mpl/aux_/yes_no.hpp>
#include <ndnboost/mpl/aux_/type_wrapper.hpp>
#include <ndnboost/mpl/aux_/nttp_decl.hpp>
#include <ndnboost/mpl/aux_/config/ctps.hpp>
#include <ndnboost/mpl/aux_/config/static_constant.hpp>
namespace ndnboost { namespace mpl {
#if !defined(NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
template< typename T >
struct is_placeholder
: bool_<false>
{
};
template< NDNBOOST_MPL_AUX_NTTP_DECL(int, N) >
struct is_placeholder< arg<N> >
: bool_<true>
{
};
#else
namespace aux {
aux::no_tag is_placeholder_helper(...);
template< NDNBOOST_MPL_AUX_NTTP_DECL(int, N) >
aux::yes_tag is_placeholder_helper(aux::type_wrapper< arg<N> >*);
} // namespace aux
template< typename T >
struct is_placeholder
{
static aux::type_wrapper<T>* get();
NDNBOOST_STATIC_CONSTANT(bool, value =
sizeof(aux::is_placeholder_helper(get())) == sizeof(aux::yes_tag)
);
typedef bool_<value> type;
};
#endif // NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
}}
#endif // NDNBOOST_MPL_IS_PLACEHOLDER_HPP_INCLUDED