cleanups from reviews.
#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