#if !defined(BOOST_PP_IS_ITERATING)

 ///// header body

 #ifndef BOOST_MPL_INHERIT_HPP_INCLUDED

 #define BOOST_MPL_INHERIT_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/inherit.hpp,v $

 // $Date: 2004/09/02 15:40:41 $

 // $Revision: 1.5 $

 #if !defined(BOOST_MPL_PREPROCESSING_MODE)

 #   include <boost/mpl/empty_base.hpp>

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

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

 #endif

 #include <boost/mpl/aux_/config/use_preprocessed.hpp>

 #if !defined(BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS) \

     && !defined(BOOST_MPL_PREPROCESSING_MODE)

 #   define BOOST_MPL_PREPROCESSED_HEADER inherit.hpp

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

 #else

 #   include <boost/mpl/limits/arity.hpp>

 #   include <boost/mpl/aux_/preprocessor/params.hpp>

 #   include <boost/mpl/aux_/preprocessor/default_params.hpp>

 #   include <boost/mpl/aux_/preprocessor/enum.hpp>

 #   include <boost/mpl/aux_/config/ctps.hpp>

 #   include <boost/mpl/aux_/config/dtp.hpp>

 #   include <boost/preprocessor/iterate.hpp>

 #   include <boost/preprocessor/dec.hpp>

 #   include <boost/preprocessor/cat.hpp>

 namespace boost { namespace mpl {

 // 'inherit<T1,T2,..,Tn>' metafunction; returns an unspecified class type

 // produced by public derivation from all metafunction's parameters 

 // (T1,T2,..,Tn), except the parameters of 'empty_base' class type; 

 // regardless the position and number of 'empty_base' parameters in the 

 // metafunction's argument list, derivation from them is always a no-op;

 // for instance:

 //      inherit<her>::type == her

 //      inherit<her,my>::type == struct unspecified : her, my {};

 //      inherit<empty_base,her>::type == her

 //      inherit<empty_base,her,empty_base,empty_base>::type == her

 //      inherit<her,empty_base,my>::type == struct unspecified : her, my {};

 //      inherit<empty_base,empty_base>::type == empty_base

 #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)

 template< 

       typename BOOST_MPL_AUX_NA_PARAM(T1)

     , typename BOOST_MPL_AUX_NA_PARAM(T2)

     > 

 struct inherit2

     : T1, T2

 {

     typedef inherit2 type;

     BOOST_MPL_AUX_LAMBDA_SUPPORT(2, inherit2, (T1,T2))

 };

 template< typename T1 > 

 struct inherit2<T1,empty_base>

 {

     typedef T1 type;

     BOOST_MPL_AUX_LAMBDA_SUPPORT_SPEC(2, inherit2, (T1,empty_base))

 };

 template< typename T2 > 

 struct inherit2<empty_base,T2>

 {

     typedef T2 type;

     BOOST_MPL_AUX_LAMBDA_SUPPORT_SPEC(2, inherit2, (empty_base,T2))

 };

 // needed to disambiguate the previous two in case when both 

 // T1 and T2 == empty_base

 template<> 

 struct inherit2<empty_base,empty_base>

 {

     typedef empty_base type;

     BOOST_MPL_AUX_LAMBDA_SUPPORT_SPEC(2, inherit2, (empty_base,empty_base))

 };

 #else

 namespace aux {

 template< bool C1, bool C2 >

 struct inherit2_impl

 {

     template< typename Derived, typename T1, typename T2 > struct result_ 

         : T1, T2

     {

         typedef Derived type_;

     };

 };

 template<>

 struct inherit2_impl<false,true>

 {

     template< typename Derived, typename T1, typename T2 > struct result_

         : T1

     {

         typedef T1 type_;

     };

 };

 template<>

 struct inherit2_impl<true,false>

 {

     template< typename Derived, typename T1, typename T2 > struct result_

         : T2 

     {

         typedef T2 type_;

     };

 };

 template<>

 struct inherit2_impl<true,true>

 {

     template< typename Derived, typename T1, typename T2 > struct result_

     {

         typedef T1 type_;

     };

 };

 } // namespace aux

 template< 

       typename BOOST_MPL_AUX_NA_PARAM(T1)

     , typename BOOST_MPL_AUX_NA_PARAM(T2)

     > 

 struct inherit2

     : aux::inherit2_impl<

           is_empty_base<T1>::value

         , is_empty_base<T2>::value

         >::template result_< inherit2<T1,T2>,T1,T2 >

 {

     typedef typename inherit2::type_ type;

     BOOST_MPL_AUX_LAMBDA_SUPPORT(2, inherit2, (T1,T2))

 };

 #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

 BOOST_MPL_AUX_NA_SPEC(2, inherit2)

 #define BOOST_PP_ITERATION_PARAMS_1 \

     (3,(3, BOOST_MPL_LIMIT_METAFUNCTION_ARITY, <boost/mpl/inherit.hpp>))

 #include BOOST_PP_ITERATE()

 }}

 #endif // BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS

 #endif // BOOST_MPL_INHERIT_HPP_INCLUDED

 ///// iteration

 #else

 #define n_ BOOST_PP_FRAME_ITERATION(1)

 template<

       BOOST_MPL_PP_DEFAULT_PARAMS(n_, typename T, na)

     >

 struct BOOST_PP_CAT(inherit,n_)

     : inherit2<

           typename BOOST_PP_CAT(inherit,BOOST_PP_DEC(n_))<

               BOOST_MPL_PP_PARAMS(BOOST_PP_DEC(n_), T)

             >::type

         , BOOST_PP_CAT(T,n_)

         >

 {

     BOOST_MPL_AUX_LAMBDA_SUPPORT(

           n_

         , BOOST_PP_CAT(inherit,n_)

         , (BOOST_MPL_PP_PARAMS(n_, T))

         )

 };

 BOOST_MPL_AUX_NA_SPEC(n_, BOOST_PP_CAT(inherit,n_))

 #if n_ == BOOST_MPL_LIMIT_METAFUNCTION_ARITY

 /// primary template

 template<

       BOOST_MPL_PP_DEFAULT_PARAMS(n_, typename T, empty_base)

     >

 struct inherit

     : BOOST_PP_CAT(inherit,n_)<BOOST_MPL_PP_PARAMS(n_, T)>

 {

 };

 // 'na' specialization

 template<>

 struct inherit< BOOST_MPL_PP_ENUM(5, na) >

 {

     template<

 #if !defined(BOOST_MPL_CFG_NO_DEFAULT_PARAMETERS_IN_NESTED_TEMPLATES)

           BOOST_MPL_PP_DEFAULT_PARAMS(n_, typename T, empty_base)

 #else

           BOOST_MPL_PP_PARAMS(n_, typename T)

 #endif

         >

     struct apply

         : inherit< BOOST_MPL_PP_PARAMS(n_, T) >

     {

     };

 };

 BOOST_MPL_AUX_NA_SPEC_LAMBDA(n_, inherit)

 BOOST_MPL_AUX_NA_SPEC_ARITY(n_, inherit)

 BOOST_MPL_AUX_NA_SPEC_TEMPLATE_ARITY(n_, n_, inherit)

 #endif

 #undef n_

 #endif // BOOST_PP_IS_ITERATING