phoenix/scope/local_variable.hpp

0001 /*==============================================================================
0002     Copyright (c) 2005-2010 Joel de Guzman
0003     Copyright (c) 2010-2011 Thomas Heller
0004
0005     Distributed under the Boost Software License, Version 1.0. (See accompanying
0006     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0007 ==============================================================================*/
0008 #ifndef BOOST_PHOENIX_SCOPE_LOCAL_VARIABLE_HPP
0009 #define BOOST_PHOENIX_SCOPE_LOCAL_VARIABLE_HPP
0010
0011 #include <boost/phoenix/core/limits.hpp>
0012 #include <boost/phoenix/core/call.hpp>
0013 #include <boost/phoenix/core/expression.hpp>
0014 #include <boost/phoenix/core/reference.hpp>
0015 #include <boost/phoenix/core/value.hpp>
0016 #include <boost/phoenix/scope/scoped_environment.hpp>
0017 #include <boost/phoenix/scope/detail/local_variable.hpp>
0018 #include <boost/phoenix/statement/sequence.hpp>
0019
0020 namespace boost { namespace phoenix
0021 {
0022     namespace expression
0023     {
0024         template <typename Key>
0025         struct local_variable
0026             : expression::terminal<detail::local<Key> >
0027         {
0028             typedef typename expression::terminal<detail::local<Key> >::type type;
0029
0030             static type make()
0031             {
0032                 type const e = {};
0033                 return e;
0034             }
0035         };
0036     }
0037
0038     namespace rule
0039     {
0040         struct local_variable
0041             : expression::local_variable<proto::_>
0042         {};
0043
0044         struct local_var_def
0045             : proto::assign<local_variable, meta_grammar>
0046         {};
0047     }
0048
0049     namespace result_of
0050     {
0051         template <typename Key>
0052         struct is_nullary<custom_terminal<detail::local<Key> > >
0053             : mpl::false_
0054         {};
0055     }
0056
0057     namespace detail
0058     {
0059         struct scope_is_nullary_actions
0060         {
0061             template <typename Rule, typename Dummy = void>
0062             struct when
0063                 : boost::phoenix::is_nullary::when<Rule, Dummy>
0064             {};
0065         };
0066
0067         template <typename Dummy>
0068         struct scope_is_nullary_actions::when<boost::phoenix::rule::custom_terminal, Dummy>
0069             : proto::or_<
0070                 proto::when<boost::phoenix::rule::local_variable, mpl::true_()>
0071               , proto::otherwise<
0072                     is_nullary::when<boost::phoenix::rule::custom_terminal, Dummy>
0073                 >
0074             >
0075         {};
0076
0077         struct local_var_not_found
0078         {
0079         };
0080     }
0081
0082     template<typename Key>
0083     struct is_custom_terminal<detail::local<Key> >
0084       : mpl::true_
0085     {};
0086
0087   template <typename Key>
0088   struct custom_terminal<detail::local<Key> >
0089     {
0090         template <typename Sig>
0091         struct result;
0092
0093         template <typename This, typename Local, typename Context>
0094         struct result<This(Local, Context)>
0095             : result<This(Local const &, Context)>
0096         {};
0097
0098         template <typename This, typename Local, typename Context>
0099         struct result<This(Local &, Context)>
0100         {
0101             typedef
0102                 typename remove_reference<
0103                     typename result_of::env<Context>::type
0104                 >::type
0105                 env_type;
0106
0107                 typedef typename detail::apply_local<detail::local<Key>, env_type>::type type;
0108         };
0109
0110         template <typename Local, typename Context>
0111         typename result<custom_terminal(Local const &, Context const&)>::type
0112         operator()(Local, Context const & ctx)
0113         {
0114             typedef
0115                 typename remove_reference<
0116                     typename result_of::env<Context>::type
0117                 >::type
0118                 env_type;
0119
0120                 typedef typename detail::apply_local<detail::local<Key>, env_type>::type return_type;
0121
0122             static const int index_value = detail::get_index<typename env_type::map_type, detail::local<Key> >::value;
0123
0124             typedef detail::eval_local<Key> eval_local;
0125
0126             // Detect if the return_type is for a value.
0127             //typedef typename is_value<return_type>::type is_value_type;
0128
0129             return eval_local::template get<return_type, index_value>(
0130                 phoenix::env(ctx));
0131         }
0132     };
0133
0134     namespace local_names
0135     {
0136         typedef expression::local_variable<struct _a_key>::type _a_type;
0137         typedef expression::local_variable<struct _b_key>::type _b_type;
0138         typedef expression::local_variable<struct _c_key>::type _c_type;
0139         typedef expression::local_variable<struct _d_key>::type _d_type;
0140         typedef expression::local_variable<struct _e_key>::type _e_type;
0141         typedef expression::local_variable<struct _f_key>::type _f_type;
0142         typedef expression::local_variable<struct _g_key>::type _g_type;
0143         typedef expression::local_variable<struct _h_key>::type _h_type;
0144         typedef expression::local_variable<struct _i_key>::type _i_type;
0145         typedef expression::local_variable<struct _j_key>::type _j_type;
0146         typedef expression::local_variable<struct _k_key>::type _k_type;
0147         typedef expression::local_variable<struct _l_key>::type _l_type;
0148         typedef expression::local_variable<struct _m_key>::type _m_type;
0149         typedef expression::local_variable<struct _n_key>::type _n_type;
0150         typedef expression::local_variable<struct _o_key>::type _o_type;
0151         typedef expression::local_variable<struct _p_key>::type _p_type;
0152         typedef expression::local_variable<struct _q_key>::type _q_type;
0153         typedef expression::local_variable<struct _r_key>::type _r_type;
0154         typedef expression::local_variable<struct _s_key>::type _s_type;
0155         typedef expression::local_variable<struct _t_key>::type _t_type;
0156         typedef expression::local_variable<struct _u_key>::type _u_type;
0157         typedef expression::local_variable<struct _v_key>::type _v_type;
0158         typedef expression::local_variable<struct _w_key>::type _w_type;
0159         typedef expression::local_variable<struct _x_key>::type _x_type;
0160         typedef expression::local_variable<struct _y_key>::type _y_type;
0161         typedef expression::local_variable<struct _z_key>::type _z_type;
0162
0163 #ifndef BOOST_PHOENIX_NO_PREDEFINED_TERMINALS
0164         BOOST_ATTRIBUTE_UNUSED _a_type const _a = {{{}}};
0165         BOOST_ATTRIBUTE_UNUSED _b_type const _b = {{{}}};
0166         BOOST_ATTRIBUTE_UNUSED _c_type const _c = {{{}}};
0167         BOOST_ATTRIBUTE_UNUSED _d_type const _d = {{{}}};
0168         BOOST_ATTRIBUTE_UNUSED _e_type const _e = {{{}}};
0169         BOOST_ATTRIBUTE_UNUSED _f_type const _f = {{{}}};
0170         BOOST_ATTRIBUTE_UNUSED _g_type const _g = {{{}}};
0171         BOOST_ATTRIBUTE_UNUSED _h_type const _h = {{{}}};
0172         BOOST_ATTRIBUTE_UNUSED _i_type const _i = {{{}}};
0173         BOOST_ATTRIBUTE_UNUSED _j_type const _j = {{{}}};
0174         BOOST_ATTRIBUTE_UNUSED _k_type const _k = {{{}}};
0175         BOOST_ATTRIBUTE_UNUSED _l_type const _l = {{{}}};
0176         BOOST_ATTRIBUTE_UNUSED _m_type const _m = {{{}}};
0177         BOOST_ATTRIBUTE_UNUSED _n_type const _n = {{{}}};
0178         BOOST_ATTRIBUTE_UNUSED _o_type const _o = {{{}}};
0179         BOOST_ATTRIBUTE_UNUSED _p_type const _p = {{{}}};
0180         BOOST_ATTRIBUTE_UNUSED _q_type const _q = {{{}}};
0181         BOOST_ATTRIBUTE_UNUSED _r_type const _r = {{{}}};
0182         BOOST_ATTRIBUTE_UNUSED _s_type const _s = {{{}}};
0183         BOOST_ATTRIBUTE_UNUSED _t_type const _t = {{{}}};
0184         BOOST_ATTRIBUTE_UNUSED _u_type const _u = {{{}}};
0185         BOOST_ATTRIBUTE_UNUSED _v_type const _v = {{{}}};
0186         BOOST_ATTRIBUTE_UNUSED _w_type const _w = {{{}}};
0187         BOOST_ATTRIBUTE_UNUSED _x_type const _x = {{{}}};
0188         BOOST_ATTRIBUTE_UNUSED _y_type const _y = {{{}}};
0189         BOOST_ATTRIBUTE_UNUSED _z_type const _z = {{{}}};
0190 #endif
0191     }
0192 }}
0193
0194 #endif