text: 
  #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.
  
  // $Source$
  // $Date: 2004-09-02 17:41:37 +0200 (jeu., 02 sept. 2004) $
  // $Revision: 24874 $
  
  #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
  