/////////////////////////////////////////////////////////////////////////////// /// \file repeat.hpp /// Contains macros to ease the generation of repetitious code constructs // // 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) #ifndef BOOST_PROTO_REPEAT_HPP_EAN_11_24_2008 #define BOOST_PROTO_REPEAT_HPP_EAN_11_24_2008 #include <boost/preprocessor/cat.hpp> #include <boost/preprocessor/facilities/intercept.hpp> #include <boost/preprocessor/repetition/enum.hpp> #include <boost/preprocessor/repetition/enum_params.hpp> #include <boost/preprocessor/repetition/enum_binary_params.hpp> #include <boost/preprocessor/iteration/local.hpp> #include <boost/preprocessor/tuple/elem.hpp> #include <boost/proto/proto_fwd.hpp> // for BOOST_PROTO_MAX_ARITY //////////////////////////////////////////// /// INTERNAL ONLY #define BOOST_PROTO_ref_a_aux(Z, N, DATA)\ boost::ref(BOOST_PP_CAT(proto_a, N)) /// \brief Generates a sequence like <tt>typename A0, typename A1, ...</tt> /// #define BOOST_PROTO_typename_A(N)\ BOOST_PP_ENUM_PARAMS(N, typename proto_A) /// \brief Generates a sequence like <tt>A0 const &, A1 const &, ...</tt> /// #define BOOST_PROTO_A_const_ref(N)\ BOOST_PP_ENUM_BINARY_PARAMS(N, proto_A, const & BOOST_PP_INTERCEPT) /// \brief Generates a sequence like <tt>A0 &, A1 &, ...</tt> /// #define BOOST_PROTO_A_ref(N)\ BOOST_PP_ENUM_BINARY_PARAMS(N, proto_A, & BOOST_PP_INTERCEPT) /// \brief Generates a sequence like <tt>A0, A1, ...</tt> /// #define BOOST_PROTO_A(N)\ BOOST_PP_ENUM_PARAMS(N, proto_A) /// \brief Generates a sequence like <tt>A0 const, A1 const, ...</tt> /// #define BOOST_PROTO_A_const(N)\ BOOST_PP_ENUM_PARAMS(N, const proto_A) /// \brief Generates a sequence like <tt>A0 const &a0, A1 const &a0, ...</tt> /// #define BOOST_PROTO_A_const_ref_a(N)\ BOOST_PP_ENUM_BINARY_PARAMS(N, proto_A, const &proto_a) /// \brief Generates a sequence like <tt>A0 &a0, A1 &a0, ...</tt> /// #define BOOST_PROTO_A_ref_a(N)\ BOOST_PP_ENUM_BINARY_PARAMS(N, proto_A, &proto_a) /// \brief Generates a sequence like <tt>boost::ref(a0), boost::ref(a1), ...</tt> /// #define BOOST_PROTO_ref_a(N)\ BOOST_PP_ENUM(N, BOOST_PROTO_ref_a_aux, ~) /// \brief Generates a sequence like <tt>a0, a1, ...</tt> /// #define BOOST_PROTO_a(N)\ BOOST_PP_ENUM_PARAMS(N, proto_a) //////////////////////////////////////////// /// INTERNAL ONLY #define BOOST_PROTO_invoke(Z, N, DATA)\ BOOST_PP_TUPLE_ELEM(5,0,DATA)(N, BOOST_PP_TUPLE_ELEM(5,1,DATA), BOOST_PP_TUPLE_ELEM(5,2,DATA), BOOST_PP_TUPLE_ELEM(5,3,DATA), BOOST_PP_TUPLE_ELEM(5,4,DATA)) /// \brief Repeatedly invoke the specified macro. /// /// BOOST_PROTO_REPEAT_FROM_TO_EX() is used generate the kind of repetitive code that is typical /// of EDSLs built with Proto. BOOST_PROTO_REPEAT_FROM_TO_EX(FROM, TO, MACRO, typename_A, A, A_a, a) is equivalent to: /// /// \code /// MACRO(FROM, typename_A, A, A_a, a) /// MACRO(FROM+1, typename_A, A, A_a, a) /// ... /// MACRO(TO-1, typename_A, A, A_a, a) /// \endcode #define BOOST_PROTO_REPEAT_FROM_TO_EX(FROM, TO, MACRO, typename_A, A, A_a, a)\ BOOST_PP_REPEAT_FROM_TO(FROM, TO, BOOST_PROTO_invoke, (MACRO, typename_A, A, A_a, a)) /// \brief Repeatedly invoke the specified macro. /// /// BOOST_PROTO_REPEAT_FROM_TO() is used generate the kind of repetitive code that is typical /// of EDSLs built with Proto. BOOST_PROTO_REPEAT_FROM_TO(FROM, TO, MACRO) is equivalent to: /// /// \code /// MACRO(FROM, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// MACRO(FROM+1, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// ... /// MACRO(TO-1, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// \endcode /// /// Example: /// /** \code // Generate BOOST_PROTO_MAX_ARITY-1 overloads of the // following construct() function template. #define M0(N, typename_A, A_const_ref, A_const_ref_a, ref_a) \ template<typename T, typename_A(N)> \ typename proto::result_of::make_expr< \ proto::tag::function \ , construct_helper<T> \ , A_const_ref(N) \ >::type const \ construct(A_const_ref_a(N)) \ { \ return proto::make_expr< \ proto::tag::function \ >( \ construct_helper<T>() \ , ref_a(N) \ ); \ } BOOST_PROTO_REPEAT_FROM_TO(1, BOOST_PROTO_MAX_ARITY, M0) #undef M0 \endcode **/ /// The above invocation of BOOST_PROTO_REPEAT_FROM_TO() will generate /// the following code: /// /// \code /// template<typename T, typename A0> /// typename proto::result_of::make_expr< /// proto::tag::function /// , construct_helper<T> /// , A0 const & /// >::type const /// construct(A0 const & a0) /// { /// return proto::make_expr< /// proto::tag::function /// >( /// construct_helper<T>() /// , boost::ref(a0) /// ); /// } /// /// template<typename T, typename A0, typename A1> /// typename proto::result_of::make_expr< /// proto::tag::function /// , construct_helper<T> /// , A0 const & /// , A1 const & /// >::type const /// construct(A0 const & a0, A1 const & a1) /// { /// return proto::make_expr< /// proto::tag::function /// >( /// construct_helper<T>() /// , boost::ref(a0) /// , boost::ref(a1) /// ); /// } /// /// // ... and so on, up to BOOST_PROTO_MAX_ARITY-1 arguments ... /// \endcode #define BOOST_PROTO_REPEAT_FROM_TO(FROM, TO, MACRO)\ BOOST_PROTO_REPEAT_FROM_TO_EX(FROM, TO, MACRO, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// \brief Repeatedly invoke the specified macro. /// /// BOOST_PROTO_REPEAT_EX() is used generate the kind of repetitive code that is typical /// of EDSLs built with Proto. BOOST_PROTO_REPEAT_EX(MACRO, typename_A, A, A_a, a) is equivalent to: /// /// \code /// MACRO(1, typename_A, A, A_a, a) /// MACRO(2, typename_A, A, A_a, a) /// ... /// MACRO(BOOST_PROTO_MAX_ARITY, typename_A, A, A_a, a) /// \endcode #define BOOST_PROTO_REPEAT_EX(MACRO, typename_A, A, A_a, a)\ BOOST_PROTO_REPEAT_FROM_TO_EX(1, BOOST_PP_INC(BOOST_PROTO_MAX_ARITY), MACRO, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// \brief Repeatedly invoke the specified macro. /// /// BOOST_PROTO_REPEAT() is used generate the kind of repetitive code that is typical /// of EDSLs built with Proto. BOOST_PROTO_REPEAT(MACRO) is equivalent to: /// /// \code /// MACRO(1, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// MACRO(2, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// ... /// MACRO(BOOST_PROTO_MAX_ARITY, BOOST_PROTO_typename_A, BOOST_PROTO_A_const_ref, BOOST_PROTO_A_const_ref_a, BOOST_PROTO_ref_a) /// \endcode #define BOOST_PROTO_REPEAT(MACRO)\ BOOST_PROTO_REPEAT_FROM_TO(1, BOOST_PP_INC(BOOST_PROTO_MAX_ARITY), MACRO) /// \brief Repeatedly invoke the specified macro. /// /// BOOST_PROTO_LOCAL_ITERATE() is used generate the kind of repetitive code that is typical /// of EDSLs built with Proto. This macro causes the user-defined macro BOOST_PROTO_LOCAL_MACRO to /// be expanded with values in the range specified by BOOST_PROTO_LOCAL_LIMITS. /// /// Usage: /// /// \code /// #include BOOST_PROTO_LOCAL_ITERATE() /// \endcode /// /// Example: /// /** \code // Generate BOOST_PROTO_MAX_ARITY-1 overloads of the // following construct() function template. #define BOOST_PROTO_LOCAL_MACRO(N, typename_A, A_const_ref, \ A_const_ref_a, ref_a) \ template<typename T, typename_A(N)> \ typename proto::result_of::make_expr< \ proto::tag::function \ , construct_helper<T> \ , A_const_ref(N) \ >::type const \ construct(A_const_ref_a(N)) \ { \ return proto::make_expr< \ proto::tag::function \ >( \ construct_helper<T>() \ , ref_a(N) \ ); \ } #define BOOST_PROTO_LOCAL_LIMITS (1, BOOST_PP_DEC(BOOST_PROTO_MAX_ARITY)) #include BOOST_PROTO_LOCAL_ITERATE() \endcode **/ /// The above inclusion of BOOST_PROTO_LOCAL_ITERATE() will generate /// the following code: /// /// \code /// template<typename T, typename A0> /// typename proto::result_of::make_expr< /// proto::tag::function /// , construct_helper<T> /// , A0 const & /// >::type const /// construct(A0 const & a0) /// { /// return proto::make_expr< /// proto::tag::function /// >( /// construct_helper<T>() /// , boost::ref(a0) /// ); /// } /// /// template<typename T, typename A0, typename A1> /// typename proto::result_of::make_expr< /// proto::tag::function /// , construct_helper<T> /// , A0 const & /// , A1 const & /// >::type const /// construct(A0 const & a0, A1 const & a1) /// { /// return proto::make_expr< /// proto::tag::function /// >( /// construct_helper<T>() /// , boost::ref(a0) /// , boost::ref(a1) /// ); /// } /// /// // ... and so on, up to BOOST_PROTO_MAX_ARITY-1 arguments ... /// \endcode /// /// If BOOST_PROTO_LOCAL_LIMITS is not defined by the user, it defaults /// to (1, BOOST_PROTO_MAX_ARITY) /// /// At each iteration, BOOST_PROTO_LOCAL_MACRO is invoked with the current /// iteration number and the following 4 macro parameters: /// /// \li BOOST_PROTO_LOCAL_typename_A /// \li BOOST_PROTO_LOCAL_A /// \li BOOST_PROTO_LOCAL_A_a /// \li BOOST_PROTO_LOCAL_a /// /// If these macros are not defined by the user, they default respectively to: /// /// \li BOOST_PROTO_typename_A /// \li BOOST_PROTO_A_const_ref /// \li BOOST_PROTO_A_const_ref_a /// \li BOOST_PROTO_ref_a /// /// After including BOOST_PROTO_LOCAL_ITERATE(), the following macros are /// automatically undefined: /// /// \li BOOST_PROTO_LOCAL_MACRO /// \li BOOST_PROTO_LOCAL_LIMITS /// \li BOOST_PROTO_LOCAL_typename_A /// \li BOOST_PROTO_LOCAL_A /// \li BOOST_PROTO_LOCAL_A_a /// \li BOOST_PROTO_LOCAL_a #define BOOST_PROTO_LOCAL_ITERATE() <boost/proto/detail/local.hpp> #endif