phoenix/scope/dynamic.hpp

0001 /*==============================================================================
0002     Copyright (c) 2001-2010 Joel de Guzman
0003     Copyright (c) 2004 Daniel Wallin
0004     Copyright (c) 2010 Thomas Heller
0005
0006     Distributed under the Boost Software License, Version 1.0. (See accompanying
0007     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0008 ==============================================================================*/
0009 #ifndef BOOST_PHOENIX_SCOPE_DYNAMIC_HPP
0010 #define BOOST_PHOENIX_SCOPE_DYNAMIC_HPP
0011
0012 #include <boost/phoenix/core/limits.hpp>
0013 #include <boost/assert.hpp>
0014 #include <boost/noncopyable.hpp>
0015 #include <boost/fusion/sequence/intrinsic/at.hpp>
0016 #include <boost/phoenix/core/expression.hpp>
0017 #include <boost/phoenix/core/meta_grammar.hpp>
0018 #include <boost/phoenix/core/call.hpp>
0019 #include <boost/phoenix/support/iterate.hpp>
0020 #include <boost/preprocessor/seq/for_each.hpp>
0021 #include <boost/preprocessor/seq/fold_left.hpp>
0022 #include <boost/preprocessor/punctuation/comma.hpp>
0023 #include <boost/type_traits/remove_pointer.hpp>
0024
0025 #define BOOST_PHOENIX_DYNAMIC_TEMPLATE_PARAMS(R, DATA, I, ELEM)                 \
0026       BOOST_PP_COMMA_IF(I) BOOST_PP_TUPLE_ELEM(2, 0, ELEM)                      \
0027 /**/
0028
0029 #define BOOST_PHOENIX_DYNAMIC_CTOR_INIT(R, DATA, I, ELEM)                       \
0030     BOOST_PP_COMMA_IF(I) BOOST_PP_TUPLE_ELEM(2, 1, ELEM)(init<I>(this))         \
0031 /**/
0032
0033 #define BOOST_PHOENIX_DYNAMIC_MEMBER(R, DATA, I, ELEM)                          \
0034     BOOST_PP_CAT(member, BOOST_PP_INC(I)) BOOST_PP_TUPLE_ELEM(2, 1, ELEM);      \
0035 /**/
0036
0037 #define BOOST_PHOENIX_DYNAMIC_FILLER_0(X, Y)                                    \
0038     ((X, Y)) BOOST_PHOENIX_DYNAMIC_FILLER_1                                     \
0039 /**/
0040
0041 #define BOOST_PHOENIX_DYNAMIC_FILLER_1(X, Y)                                    \
0042     ((X, Y)) BOOST_PHOENIX_DYNAMIC_FILLER_0                                     \
0043 /**/
0044
0045 #define BOOST_PHOENIX_DYNAMIC_FILLER_0_END
0046 #define BOOST_PHOENIX_DYNAMIC_FILLER_1_END
0047
0048 #define BOOST_PHOENIX_DYNAMIC_BASE(NAME, MEMBER)                                \
0049 struct NAME                                                                     \
0050     : ::boost::phoenix::dynamic<                                                \
0051         BOOST_PP_SEQ_FOR_EACH_I(                                                \
0052                 BOOST_PHOENIX_DYNAMIC_TEMPLATE_PARAMS                           \
0053               , _                                                               \
0054               , MEMBER)                                                         \
0055     >                                                                           \
0056 {                                                                               \
0057     NAME()                                                                      \
0058         : BOOST_PP_SEQ_FOR_EACH_I(BOOST_PHOENIX_DYNAMIC_CTOR_INIT, _, MEMBER)   \
0059     {}                                                                          \
0060                                                                                 \
0061     BOOST_PP_SEQ_FOR_EACH_I(BOOST_PHOENIX_DYNAMIC_MEMBER, _, MEMBER)            \
0062 }                                                                               \
0063 /**/
0064
0065 #define BOOST_PHOENIX_DYNAMIC(NAME, MEMBER)                                     \
0066     BOOST_PHOENIX_DYNAMIC_BASE(                                                 \
0067         NAME                                                                    \
0068       , BOOST_PP_CAT(BOOST_PHOENIX_DYNAMIC_FILLER_0 MEMBER,_END)                \
0069     )                                                                           \
0070 /**/
0071
0072 BOOST_PHOENIX_DEFINE_EXPRESSION(
0073     (boost)(phoenix)(dynamic_member)
0074   , (proto::terminal<proto::_>)
0075     (proto::terminal<proto::_>)
0076 )
0077
0078 namespace boost { namespace phoenix
0079 {
0080     template <typename DynamicScope>
0081     struct dynamic_frame : noncopyable
0082     {
0083         typedef typename DynamicScope::tuple_type tuple_type;
0084
0085         dynamic_frame(DynamicScope const& s)
0086             : tuple()
0087             , save(s.frame)
0088             , scope(s)
0089         {
0090             scope.frame = this;
0091         }
0092
0093         template <typename Tuple>
0094         dynamic_frame(DynamicScope const& s, Tuple const& init)
0095             : tuple(init)
0096             , save(s.frame)
0097             , scope(s)
0098         {
0099             scope.frame = this;
0100         }
0101
0102         ~dynamic_frame()
0103         {
0104             scope.frame = save;
0105         }
0106
0107         tuple_type& data() { return tuple; }
0108         tuple_type const& data() const { return tuple; }
0109
0110         private:
0111             tuple_type tuple;
0112             dynamic_frame *save;
0113             DynamicScope const& scope;
0114     };
0115
0116     struct dynamic_member_eval
0117     {
0118         template <typename Sig>
0119         struct result;
0120
0121         template <typename This, typename N, typename Scope, typename Context>
0122         struct result<This(N, Scope, Context)>
0123         {
0124             typedef
0125                 typename boost::remove_pointer<
0126                     typename proto::detail::uncvref<
0127                         typename proto::result_of::value<Scope>::type
0128                     >::type
0129                 >::type
0130                 scope_type;
0131             typedef
0132                 typename scope_type::dynamic_frame_type::tuple_type
0133                 tuple_type;
0134
0135             typedef
0136                 typename fusion::result_of::at_c<
0137                     tuple_type
0138                   , proto::detail::uncvref<
0139                         typename proto::result_of::value<N>::type
0140                     >::type::value
0141                 >::type
0142                 type;
0143
0144         };
0145
0146         template <typename N, typename Scope, typename Context>
0147         typename result<dynamic_member_eval(N, Scope, Context)>::type
0148         operator()(N, Scope s, Context const &) const
0149         {
0150             return
0151                 fusion::at_c<
0152                     proto::detail::uncvref<
0153                         typename proto::result_of::value<N>::type
0154                     >::type::value
0155                 >(
0156                     proto::value(s)->frame->data()
0157                 );
0158         }
0159     };
0160
0161     template <typename Dummy>
0162     struct default_actions::when<rule::dynamic_member, Dummy>
0163         : call<dynamic_member_eval>
0164     {};
0165
0166 //#if defined(BOOST_PHOENIX_NO_VARIADIC_SCOPE)
0167     template <
0168         BOOST_PHOENIX_typename_A_void(BOOST_PHOENIX_DYNAMIC_LIMIT)
0169       , typename Dummy = void
0170     >
0171     struct dynamic;
0172
0173     // Bring in the rest ...
0174     #include <boost/phoenix/scope/detail/cpp03/dynamic.hpp>
0175 //#else
0176 //    // TODO:
0177 //#endif
0178 }}
0179
0180 #endif