You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

211 lines
5.7 KiB

3 years ago
#ifndef BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED
#define BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED
// Copyright Aleksey Gurtovoy 2001-2004
// Copyright David Abrahams 2001-2002
//
// 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.
// $Id$
// $Date$
// $Revision$
#if !defined(BOOST_MPL_PREPROCESSING_MODE)
# include <boost/mpl/identity.hpp>
# include <boost/mpl/next.hpp>
# include <boost/mpl/if.hpp>
# include <boost/mpl/apply.hpp>
# include <boost/mpl/aux_/value_wknd.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 iter_fold_if_impl.hpp
# include <boost/mpl/aux_/include_preprocessed.hpp>
#else
# include <boost/mpl/limits/unrolling.hpp>
# include <boost/preprocessor/arithmetic/sub.hpp>
# include <boost/preprocessor/repeat.hpp>
# include <boost/preprocessor/inc.hpp>
# include <boost/preprocessor/dec.hpp>
# include <boost/preprocessor/cat.hpp>
namespace boost { namespace mpl { namespace aux {
template< typename Iterator, typename State >
struct iter_fold_if_null_step
{
typedef State state;
typedef Iterator iterator;
};
template< bool >
struct iter_fold_if_step_impl
{
template<
typename Iterator
, typename State
, typename StateOp
, typename IteratorOp
>
struct result_
{
typedef typename apply2<StateOp,State,Iterator>::type state;
typedef typename IteratorOp::type iterator;
};
};
template<>
struct iter_fold_if_step_impl<false>
{
template<
typename Iterator
, typename State
, typename StateOp
, typename IteratorOp
>
struct result_
{
typedef State state;
typedef Iterator iterator;
};
};
// agurt, 25/jun/02: MSVC 6.5 workaround, had to get rid of inheritance
// here and in 'iter_fold_if_backward_step', because sometimes it interfered
// with the "early template instantiation bug" in _really_ ugly ways
template<
typename Iterator
, typename State
, typename ForwardOp
, typename Predicate
>
struct iter_fold_if_forward_step
{
typedef typename apply2<Predicate,State,Iterator>::type not_last;
typedef typename iter_fold_if_step_impl<
BOOST_MPL_AUX_MSVC_VALUE_WKND(not_last)::value
>::template result_< Iterator,State,ForwardOp,mpl::next<Iterator> > impl_;
typedef typename impl_::state state;
typedef typename impl_::iterator iterator;
};
template<
typename Iterator
, typename State
, typename BackwardOp
, typename Predicate
>
struct iter_fold_if_backward_step
{
typedef typename apply2<Predicate,State,Iterator>::type not_last;
typedef typename iter_fold_if_step_impl<
BOOST_MPL_AUX_MSVC_VALUE_WKND(not_last)::value
>::template result_< Iterator,State,BackwardOp,identity<Iterator> > impl_;
typedef typename impl_::state state;
typedef typename impl_::iterator iterator;
};
// local macros, #undef-ined at the end of the header
# define AUX_ITER_FOLD_FORWARD_STEP(unused, i, unused2) \
typedef iter_fold_if_forward_step< \
typename BOOST_PP_CAT(forward_step,i)::iterator \
, typename BOOST_PP_CAT(forward_step,i)::state \
, ForwardOp \
, ForwardPredicate \
> BOOST_PP_CAT(forward_step, BOOST_PP_INC(i)); \
/**/
# define AUX_ITER_FOLD_BACKWARD_STEP_FUNC(i) \
typedef iter_fold_if_backward_step< \
typename BOOST_PP_CAT(forward_step,BOOST_PP_DEC(i))::iterator \
, typename BOOST_PP_CAT(backward_step,i)::state \
, BackwardOp \
, BackwardPredicate \
> BOOST_PP_CAT(backward_step,BOOST_PP_DEC(i)); \
/**/
# define AUX_ITER_FOLD_BACKWARD_STEP(unused, i, unused2) \
AUX_ITER_FOLD_BACKWARD_STEP_FUNC( \
BOOST_PP_SUB_D(1,BOOST_MPL_LIMIT_UNROLLING,i) \
) \
/**/
# define AUX_LAST_FORWARD_STEP \
BOOST_PP_CAT(forward_step, BOOST_MPL_LIMIT_UNROLLING) \
/**/
# define AUX_LAST_BACKWARD_STEP \
BOOST_PP_CAT(backward_step, BOOST_MPL_LIMIT_UNROLLING) \
/**/
template<
typename Iterator
, typename State
, typename ForwardOp
, typename ForwardPredicate
, typename BackwardOp
, typename BackwardPredicate
>
struct iter_fold_if_impl
{
private:
typedef iter_fold_if_null_step<Iterator,State> forward_step0;
BOOST_PP_REPEAT(
BOOST_MPL_LIMIT_UNROLLING
, AUX_ITER_FOLD_FORWARD_STEP
, unused
)
typedef typename if_<
typename AUX_LAST_FORWARD_STEP::not_last
, iter_fold_if_impl<
typename AUX_LAST_FORWARD_STEP::iterator
, typename AUX_LAST_FORWARD_STEP::state
, ForwardOp
, ForwardPredicate
, BackwardOp
, BackwardPredicate
>
, iter_fold_if_null_step<
typename AUX_LAST_FORWARD_STEP::iterator
, typename AUX_LAST_FORWARD_STEP::state
>
>::type AUX_LAST_BACKWARD_STEP;
BOOST_PP_REPEAT(
BOOST_MPL_LIMIT_UNROLLING
, AUX_ITER_FOLD_BACKWARD_STEP
, unused
)
public:
typedef typename backward_step0::state state;
typedef typename AUX_LAST_BACKWARD_STEP::iterator iterator;
};
# undef AUX_LAST_BACKWARD_STEP
# undef AUX_LAST_FORWARD_STEP
# undef AUX_ITER_FOLD_BACKWARD_STEP
# undef AUX_ITER_FOLD_BACKWARD_STEP_FUNC
# undef AUX_ITER_FOLD_FORWARD_STEP
}}}
#endif // BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS
#endif // BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED