//-----------------------------------------------------------------------------
// boost mpl/aux_/iter_fold_if_impl.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2001-02
// Aleksey Gurtovoy, David Abrahams
//
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee,
// provided that the above copyright notice appears in all copies and
// that both the copyright notice and this permission notice appear in
// supporting documentation. No representations are made about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
#ifndef BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED
#define BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED
#include "boost/mpl/aux_/apply.hpp"
#if !defined(BOOST_MPL_PREPROCESSING_MODE)
# include "boost/mpl/identity.hpp"
# include "boost/mpl/next.hpp"
# include "boost/mpl/if.hpp"
# include "boost/mpl/aux_/value_wknd.hpp"
# include "boost/mpl/aux_/bool_value_wknd.hpp"
#endif
#include "boost/mpl/aux_/config/use_preprocessed.hpp"
#if !defined(BOOST_MPL_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 BOOST_MPL_AUX_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 BOOST_MPL_AUX_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 BOOST_MPL_AUX_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_UNROLLING_LIMIT,i) \
) \
/**/
# define AUX_LAST_FORWARD_STEP \
BOOST_PP_CAT(forward_step, BOOST_MPL_UNROLLING_LIMIT) \
/**/
# define AUX_LAST_BACKWARD_STEP \
BOOST_PP_CAT(backward_step, BOOST_MPL_UNROLLING_LIMIT) \
/**/
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_1(
BOOST_MPL_UNROLLING_LIMIT
, 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_1(
BOOST_MPL_UNROLLING_LIMIT
, 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
} // namespace aux
} // namespace mpl
} // namespace boost
#endif // BOOST_MPL_USE_PREPROCESSED_HEADERS
#endif // BOOST_MPL_AUX_ITER_FOLD_IF_IMPL_HPP_INCLUDED