#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.

// $Id: inherit.hpp 49267 2008-10-11 06:19:02Z agurtovoy $

// $Date: 2008-10-11 02:19:02 -0400 (Sat, 11 Oct 2008) $

// $Revision: 49267 $

#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