#ifndef BOOST_MPL_AUX_NA_FWD_HPP_INCLUDED

 #define BOOST_MPL_AUX_NA_FWD_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.

 // $Source: /cvsroot/boost/boost/boost/mpl/aux_/na_fwd.hpp,v $

 // $Date: 2004/11/28 01:37:30 $

 // $Revision: 1.2 $

 #include <boost/mpl/aux_/adl_barrier.hpp>

 BOOST_MPL_AUX_ADL_BARRIER_NAMESPACE_OPEN

 // n.a. == not available

 struct na

 {

     typedef na type;

     enum { value = 0 };

 };

 BOOST_MPL_AUX_ADL_BARRIER_NAMESPACE_CLOSE

 BOOST_MPL_AUX_ADL_BARRIER_DECL(na)

 #endif // BOOST_MPL_AUX_NA_FWD_HPP_INCLUDED