proto/detail/basic_expr.hpp

0001 #if !defined(BOOST_PROTO_DONT_USE_PREPROCESSED_FILES)
0002
0003     #include <boost/proto/detail/preprocessed/basic_expr.hpp>
0004
0005 #elif !defined(BOOST_PP_IS_ITERATING)
0006
0007     /// INTERNAL ONLY
0008     ///
0009     #define BOOST_PROTO_CHILD(Z, N, DATA)                                                       \
0010         typedef BOOST_PP_CAT(Arg, N) BOOST_PP_CAT(proto_child, N);                              \
0011         BOOST_PP_CAT(proto_child, N) BOOST_PP_CAT(child, N);                                    \
0012         /**< INTERNAL ONLY */
0013
0014     /// INTERNAL ONLY
0015     ///
0016     #define BOOST_PROTO_VOID(Z, N, DATA)                                                        \
0017         typedef void BOOST_PP_CAT(proto_child, N);                                              \
0018         /**< INTERNAL ONLY */
0019
0020     #if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
0021         #pragma wave option(preserve: 2, line: 0, output: "preprocessed/basic_expr.hpp")
0022     #endif
0023
0024     ///////////////////////////////////////////////////////////////////////////////
0025     /// \file basic_expr.hpp
0026     /// Contains definition of basic_expr\<\> class template.
0027     //
0028     //  Copyright 2008 Eric Niebler. Distributed under the Boost
0029     //  Software License, Version 1.0. (See accompanying file
0030     //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0031
0032     #if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
0033         #pragma wave option(preserve: 1)
0034     #endif
0035
0036     // The expr<> specializations are actually defined here.
0037     #define BOOST_PROTO_DEFINE_TERMINAL
0038     #define BOOST_PP_ITERATION_PARAMS_1 (3, (0, 0, <boost/proto/detail/basic_expr.hpp>))
0039     #include BOOST_PP_ITERATE()
0040
0041     #undef BOOST_PROTO_DEFINE_TERMINAL
0042     #define BOOST_PP_ITERATION_PARAMS_1 (3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/detail/basic_expr.hpp>))
0043     #include BOOST_PP_ITERATE()
0044
0045     #if defined(__WAVE__) && defined(BOOST_PROTO_CREATE_PREPROCESSED_FILES)
0046         #pragma wave option(output: null)
0047     #endif
0048
0049     #undef BOOST_PROTO_CHILD
0050     #undef BOOST_PROTO_VOID
0051
0052 #else
0053
0054     #define ARG_COUNT BOOST_PP_MAX(1, BOOST_PP_ITERATION())
0055
0056     /// \brief Simplified representation of a node in an expression tree.
0057     ///
0058     /// \c proto::basic_expr\<\> is a node in an expression template tree. It
0059     /// is a container for its child sub-trees. It also serves as
0060     /// the terminal nodes of the tree.
0061     ///
0062     /// \c Tag is type that represents the operation encoded by
0063     ///             this expression. It is typically one of the structs
0064     ///             in the \c boost::proto::tag namespace, but it doesn't
0065     ///             have to be.
0066     ///
0067     /// \c Args is a type list representing the type of the children
0068     ///             of this expression. It is an instantiation of one
0069     ///             of \c proto::list1\<\>, \c proto::list2\<\>, etc. The
0070     ///             child types must all themselves be either \c expr\<\>
0071     ///             or <tt>proto::expr\<\>&</tt>. If \c Args is an
0072     ///             instantiation of \c proto::term\<\> then this
0073     ///             \c expr\<\> type represents a terminal expression;
0074     ///             the parameter to the \c proto::term\<\> template
0075     ///             represents the terminal's value type.
0076     ///
0077     /// \c Arity is an integral constant representing the number of child
0078     ///             nodes this node contains. If \c Arity is 0, then this
0079     ///             node is a terminal.
0080     ///
0081     /// \c proto::basic_expr\<\> is a valid Fusion random-access sequence, where
0082     /// the elements of the sequence are the child expressions.
0083     #ifdef BOOST_PROTO_DEFINE_TERMINAL
0084     template<typename Tag, typename Arg0>
0085     struct basic_expr<Tag, term<Arg0>, 0>
0086     #else
0087     template<typename Tag BOOST_PP_ENUM_TRAILING_PARAMS(ARG_COUNT, typename Arg)>
0088     struct basic_expr<Tag, BOOST_PP_CAT(list, BOOST_PP_ITERATION())<BOOST_PP_ENUM_PARAMS(ARG_COUNT, Arg)>, BOOST_PP_ITERATION() >
0089     #endif
0090     {
0091         typedef Tag proto_tag;
0092         static const long proto_arity_c = BOOST_PP_ITERATION();
0093         typedef mpl::long_<BOOST_PP_ITERATION() > proto_arity;
0094         typedef basic_expr proto_base_expr;
0095         #ifdef BOOST_PROTO_DEFINE_TERMINAL
0096         typedef term<Arg0> proto_args;
0097         #else
0098         typedef BOOST_PP_CAT(list, BOOST_PP_ITERATION())<BOOST_PP_ENUM_PARAMS(ARG_COUNT, Arg)> proto_args;
0099         #endif
0100         typedef basic_expr proto_grammar;
0101         typedef basic_default_domain proto_domain;
0102         typedef default_generator proto_generator;
0103         typedef proto::tag::proto_expr<Tag, proto_domain> fusion_tag;
0104         typedef basic_expr proto_derived_expr;
0105         typedef void proto_is_expr_; /**< INTERNAL ONLY */
0106
0107         BOOST_PP_REPEAT(ARG_COUNT, BOOST_PROTO_CHILD, ~)
0108         BOOST_PP_REPEAT_FROM_TO(ARG_COUNT, BOOST_PROTO_MAX_ARITY, BOOST_PROTO_VOID, ~)
0109
0110         /// \return *this
0111         ///
0112         BOOST_FORCEINLINE
0113         basic_expr const &proto_base() const
0114         {
0115             return *this;
0116         }
0117
0118         /// \overload
0119         ///
0120         BOOST_FORCEINLINE
0121         basic_expr &proto_base()
0122         {
0123             return *this;
0124         }
0125
0126     #ifdef BOOST_PROTO_DEFINE_TERMINAL
0127         /// \return A new \c expr\<\> object initialized with the specified
0128         /// arguments.
0129         ///
0130         template<typename A0>
0131         BOOST_FORCEINLINE
0132         static basic_expr const make(A0 &a0)
0133         {
0134             return detail::make_terminal(a0, static_cast<basic_expr *>(0), static_cast<proto_args *>(0));
0135         }
0136
0137         /// \overload
0138         ///
0139         template<typename A0>
0140         BOOST_FORCEINLINE
0141         static basic_expr const make(A0 const &a0)
0142         {
0143             return detail::make_terminal(a0, static_cast<basic_expr *>(0), static_cast<proto_args *>(0));
0144         }
0145     #else
0146         /// \return A new \c expr\<\> object initialized with the specified
0147         /// arguments.
0148         ///
0149         template<BOOST_PP_ENUM_PARAMS(ARG_COUNT, typename A)>
0150         BOOST_FORCEINLINE
0151         static basic_expr const make(BOOST_PP_ENUM_BINARY_PARAMS(ARG_COUNT, A, const &a))
0152         {
0153             basic_expr that = {BOOST_PP_ENUM_PARAMS(ARG_COUNT, a)};
0154             return that;
0155         }
0156     #endif
0157
0158     #if 1 == BOOST_PP_ITERATION()
0159         /// If \c Tag is \c boost::proto::tag::address_of and \c proto_child0 is
0160         /// <tt>T&</tt>, then \c address_of_hack_type_ is <tt>T*</tt>.
0161         /// Otherwise, it is some undefined type.
0162         typedef typename detail::address_of_hack<Tag, proto_child0>::type address_of_hack_type_;
0163
0164         /// \return The address of <tt>this->child0</tt> if \c Tag is
0165         /// \c boost::proto::tag::address_of. Otherwise, this function will
0166         /// fail to compile.
0167         ///
0168         /// \attention Proto overloads <tt>operator&</tt>, which means that
0169         /// proto-ified objects cannot have their addresses taken, unless we use
0170         /// the following hack to make \c &x implicitly convertible to \c X*.
0171         BOOST_FORCEINLINE
0172         operator address_of_hack_type_() const
0173         {
0174             return boost::addressof(this->child0);
0175         }
0176     #else
0177         /// INTERNAL ONLY
0178         ///
0179         typedef detail::not_a_valid_type address_of_hack_type_;
0180     #endif
0181     };
0182
0183 #undef ARG_COUNT
0184
0185 #endif