boost/proto/transform/detail/fold_impl.hpp
#if !defined(BOOST_PROTO_DONT_USE_PREPROCESSED_FILES)
#include <boost/proto/transform/detail/preprocessed/fold_impl.hpp>
#elif !defined(BOOST_PP_IS_ITERATING)
#define BOOST_PROTO_CHILD_N_TYPE(N) \
BOOST_PP_CAT(proto_child, N) \
/**/
#define BOOST_PROTO_FOLD_STATE_TYPE(Z, N, DATA) \
typedef \
typename when<_, Fun>::template impl< \
typename result_of::child_c<Expr, N>::type \
, BOOST_PP_CAT(state, N) \
, Data \
>::result_type \
BOOST_PP_CAT(state, BOOST_PP_INC(N)); \
/**/
#define BOOST_PROTO_FOLD_STATE(Z, N, DATA) \
BOOST_PP_CAT(state, BOOST_PP_INC(N)) \
BOOST_PP_CAT(s, BOOST_PP_INC(N)) \
= typename when<_, Fun>::template impl< \
typename result_of::child_c<Expr, N>::type \
, BOOST_PP_CAT(state, N) \
, Data \
>()( \
proto::child_c<N>(e) \
, BOOST_PP_CAT(s, N) \
, d \
); \
/**/
#define BOOST_PROTO_REVERSE_FOLD_STATE_TYPE(Z, N, DATA) \
typedef \
typename when<_, Fun>::template impl< \
typename result_of::child_c< \
Expr \
, BOOST_PP_SUB(DATA, BOOST_PP_INC(N)) \
>::type \
, BOOST_PP_CAT(state, BOOST_PP_SUB(DATA, N)) \
, Data \
>::result_type \
BOOST_PP_CAT(state, BOOST_PP_SUB(DATA, BOOST_PP_INC(N))); \
/**/
#define BOOST_PROTO_REVERSE_FOLD_STATE(Z, N, DATA) \
BOOST_PP_CAT(state, BOOST_PP_SUB(DATA, BOOST_PP_INC(N))) \
BOOST_PP_CAT(s, BOOST_PP_SUB(DATA, BOOST_PP_INC(N))) \
= typename when<_, Fun>::template impl< \
typename result_of::child_c< \
Expr \
, BOOST_PP_SUB(DATA, BOOST_PP_INC(N)) \
>::type \
, BOOST_PP_CAT(state, BOOST_PP_SUB(DATA, N)) \
, Data \
>()( \
proto::child_c<BOOST_PP_SUB(DATA, BOOST_PP_INC(N))>(e) \
, BOOST_PP_CAT(s, BOOST_PP_SUB(DATA, N)) \
, d \
); \
/**/
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
#pragma wave option(preserve: 2, line: 0, output: "preprocessed/fold_impl.hpp")
#endif
///////////////////////////////////////////////////////////////////////////////
/// \file fold_impl.hpp
/// Contains definition of fold_impl<> and reverse_fold_impl<> templates.
//
// Copyright 2008 Eric Niebler. 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)
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
#pragma wave option(preserve: 1)
#endif
#define BOOST_PP_ITERATION_PARAMS_1 \
(3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/transform/detail/fold_impl.hpp>))
#include BOOST_PP_ITERATE()
#if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
#pragma wave option(output: null)
#endif
#undef BOOST_PROTO_REVERSE_FOLD_STATE
#undef BOOST_PROTO_REVERSE_FOLD_STATE_TYPE
#undef BOOST_PROTO_FOLD_STATE
#undef BOOST_PROTO_FOLD_STATE_TYPE
#undef BOOST_PROTO_CHILD_N_TYPE
#else
#define N BOOST_PP_ITERATION()
template<typename State0, typename Fun, typename Expr, typename State, typename Data>
struct fold_impl<State0, Fun, Expr, State, Data, N>
: transform_impl<Expr, State, Data>
{
typedef typename when<_, State0>::template impl<Expr, State, Data>::result_type state0;
BOOST_PP_REPEAT(N, BOOST_PROTO_FOLD_STATE_TYPE, N)
typedef BOOST_PP_CAT(state, N) result_type;
result_type operator ()(
typename fold_impl::expr_param e
, typename fold_impl::state_param s
, typename fold_impl::data_param d
) const
{
state0 s0 =
typename when<_, State0>::template impl<Expr, State, Data>()(e, s, d);
BOOST_PP_REPEAT(N, BOOST_PROTO_FOLD_STATE, N)
return BOOST_PP_CAT(s, N);
}
};
template<typename State0, typename Fun, typename Expr, typename State, typename Data>
struct reverse_fold_impl<State0, Fun, Expr, State, Data, N>
: transform_impl<Expr, State, Data>
{
typedef typename when<_, State0>::template impl<Expr, State, Data>::result_type BOOST_PP_CAT(state, N);
BOOST_PP_REPEAT(N, BOOST_PROTO_REVERSE_FOLD_STATE_TYPE, N)
typedef state0 result_type;
result_type operator ()(
typename reverse_fold_impl::expr_param e
, typename reverse_fold_impl::state_param s
, typename reverse_fold_impl::data_param d
) const
{
BOOST_PP_CAT(state, N) BOOST_PP_CAT(s, N) =
typename when<_, State0>::template impl<Expr, State, Data>()(e, s, d);
BOOST_PP_REPEAT(N, BOOST_PROTO_REVERSE_FOLD_STATE, N)
return s0;
}
};
#undef N
#endif
