| /////////////////////////////////////////////////////////////////////////////// | |
| // extractor.hpp | |
| // | |
| // Copyright 2005 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_ACCUMULATORS_FRAMEWORK_EXTRACTOR_HPP_EAN_28_10_2005 | |
| #define BOOST_ACCUMULATORS_FRAMEWORK_EXTRACTOR_HPP_EAN_28_10_2005 | |
| #include <boost/preprocessor/tuple/rem.hpp> | |
| #include <boost/preprocessor/array/size.hpp> | |
| #include <boost/preprocessor/array/data.hpp> | |
| #include <boost/preprocessor/array/elem.hpp> | |
| #include <boost/preprocessor/seq/to_array.hpp> | |
| #include <boost/preprocessor/seq/transform.hpp> | |
| #include <boost/preprocessor/repetition/enum_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_trailing_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_trailing_binary_params.hpp> | |
| #include <boost/parameter/binding.hpp> | |
| #include <boost/mpl/apply.hpp> | |
| #include <boost/mpl/eval_if.hpp> | |
| #include <boost/type_traits/remove_reference.hpp> | |
| #include <boost/accumulators/accumulators_fwd.hpp> | |
| #include <boost/accumulators/framework/parameters/accumulator.hpp> | |
| namespace boost { namespace accumulators | |
| { | |
| namespace detail | |
| { | |
| template<typename AccumulatorSet, typename Feature> | |
| struct accumulator_set_result | |
| { | |
| typedef typename as_feature<Feature>::type feature_type; | |
| typedef typename mpl::apply<AccumulatorSet, feature_type>::type::result_type type; | |
| }; | |
| template<typename Args, typename Feature> | |
| struct argument_pack_result | |
| : accumulator_set_result< | |
| typename remove_reference< | |
| typename parameter::binding<Args, tag::accumulator>::type | |
| >::type | |
| , Feature | |
| > | |
| { | |
| }; | |
| template<typename A, typename Feature> | |
| struct extractor_result | |
| : mpl::eval_if< | |
| detail::is_accumulator_set<A> | |
| , accumulator_set_result<A, Feature> | |
| , argument_pack_result<A, Feature> | |
| > | |
| { | |
| }; | |
| template<typename Feature, typename AccumulatorSet> | |
| typename extractor_result<AccumulatorSet, Feature>::type | |
| do_extract(AccumulatorSet const &acc, mpl::true_) | |
| { | |
| typedef typename as_feature<Feature>::type feature_type; | |
| return extract_result<feature_type>(acc); | |
| } | |
| template<typename Feature, typename Args> | |
| typename extractor_result<Args, Feature>::type | |
| do_extract(Args const &args, mpl::false_) | |
| { | |
| typedef typename as_feature<Feature>::type feature_type; | |
| return find_accumulator<feature_type>(args[accumulator]).result(args); | |
| } | |
| } // namespace detail | |
| /////////////////////////////////////////////////////////////////////////////// | |
| /// Extracts the result associated with Feature from the specified accumulator_set. | |
| template<typename Feature> | |
| struct extractor | |
| { | |
| typedef extractor<Feature> this_type; | |
| /// The result meta-function for determining the return type of the extractor | |
| template<typename F> | |
| struct result; | |
| template<typename A1> | |
| struct result<this_type(A1)> | |
| : detail::extractor_result<A1, Feature> | |
| { | |
| }; | |
| /// Extract the result associated with Feature from the accumulator set | |
| /// \param acc The accumulator set object from which to extract the result | |
| template<typename Arg1> | |
| typename detail::extractor_result<Arg1, Feature>::type | |
| operator ()(Arg1 const &arg1) const | |
| { | |
| // Arg1 could be an accumulator_set or an argument pack containing | |
| // an accumulator_set. Dispatch accordingly. | |
| return detail::do_extract<Feature>(arg1, detail::is_accumulator_set<Arg1>()); | |
| } | |
| /// \overload | |
| /// | |
| /// \param a1 Optional named parameter to be passed to the accumulator's result() function. | |
| template<typename AccumulatorSet, typename A1> | |
| typename detail::extractor_result<AccumulatorSet, Feature>::type | |
| operator ()(AccumulatorSet const &acc, A1 const &a1) const | |
| { | |
| BOOST_MPL_ASSERT((detail::is_accumulator_set<AccumulatorSet>)); | |
| typedef typename as_feature<Feature>::type feature_type; | |
| return extract_result<feature_type>(acc, a1); | |
| } | |
| // ... other overloads generated by Boost.Preprocessor: | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_EXTRACTOR_FUN_OP(z, n, _) \ | |
| template<BOOST_PP_ENUM_PARAMS_Z(z, n, typename A)> \ | |
| struct result<this_type(BOOST_PP_ENUM_PARAMS_Z(z, n, A))> \ | |
| : detail::extractor_result<A1, Feature> \ | |
| {}; \ | |
| template< \ | |
| typename AccumulatorSet \ | |
| BOOST_PP_ENUM_TRAILING_PARAMS_Z(z, n, typename A) \ | |
| > \ | |
| typename detail::extractor_result<AccumulatorSet, Feature>::type \ | |
| operator ()( \ | |
| AccumulatorSet const &acc \ | |
| BOOST_PP_ENUM_TRAILING_BINARY_PARAMS_Z(z, n, A, const &a) \ | |
| ) const \ | |
| { \ | |
| BOOST_MPL_ASSERT((detail::is_accumulator_set<AccumulatorSet>)); \ | |
| typedef typename as_feature<Feature>::type feature_type; \ | |
| return extract_result<feature_type>(acc BOOST_PP_ENUM_TRAILING_PARAMS_Z(z, n, a));\ | |
| } | |
| BOOST_PP_REPEAT_FROM_TO( | |
| 2 | |
| , BOOST_PP_INC(BOOST_ACCUMULATORS_MAX_ARGS) | |
| , BOOST_ACCUMULATORS_EXTRACTOR_FUN_OP | |
| , _ | |
| ) | |
| #ifdef BOOST_ACCUMULATORS_DOXYGEN_INVOKED | |
| /// \overload | |
| /// | |
| template<typename AccumulatorSet, typename A1, typename A2, ...> | |
| typename detail::extractor_result<AccumulatorSet, Feature>::type | |
| operator ()(AccumulatorSet const &acc, A1 const &a1, A2 const &a2, ...); | |
| #endif | |
| }; | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_ARRAY_REM(Array) \ | |
| BOOST_PP_TUPLE_REM_CTOR(BOOST_PP_ARRAY_SIZE(Array), BOOST_PP_ARRAY_DATA(Array)) | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_SEQ_REM(Seq) \ | |
| BOOST_ACCUMULATORS_ARRAY_REM(BOOST_PP_SEQ_TO_ARRAY(Seq)) | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_ARGS_OP(s, data, elem) \ | |
| T ## s | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_PARAMS_OP(s, data, elem) \ | |
| elem T ## s | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_MAKE_FEATURE(Tag, Feature, ParamsSeq) \ | |
| Tag::Feature< \ | |
| BOOST_ACCUMULATORS_SEQ_REM( \ | |
| BOOST_PP_SEQ_TRANSFORM(BOOST_ACCUMULATORS_ARGS_OP, ~, ParamsSeq) \ | |
| ) \ | |
| > | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_DEFINE_EXTRACTOR_FUN_IMPL(z, n, Tag, Feature, ParamsSeq) \ | |
| template< \ | |
| BOOST_ACCUMULATORS_SEQ_REM( \ | |
| BOOST_PP_SEQ_TRANSFORM(BOOST_ACCUMULATORS_PARAMS_OP, ~, ParamsSeq) \ | |
| ) \ | |
| , typename Arg1 \ | |
| BOOST_PP_ENUM_TRAILING_PARAMS_Z(z, n, typename A) \ | |
| > \ | |
| typename boost::accumulators::detail::extractor_result< \ | |
| Arg1 \ | |
| , BOOST_ACCUMULATORS_MAKE_FEATURE(Tag, Feature, ParamsSeq) \ | |
| >::type \ | |
| Feature(Arg1 const &arg1 BOOST_PP_ENUM_TRAILING_BINARY_PARAMS_Z(z, n, A, const &a) ) \ | |
| { \ | |
| typedef BOOST_ACCUMULATORS_MAKE_FEATURE(Tag, Feature, ParamsSeq) feature_type; \ | |
| return boost::accumulators::extractor<feature_type>()( \ | |
| arg1 BOOST_PP_ENUM_TRAILING_PARAMS_Z(z, n, a)); \ | |
| } | |
| /// INTERNAL ONLY | |
| /// | |
| #define BOOST_ACCUMULATORS_DEFINE_EXTRACTOR_FUN(z, n, _) \ | |
| BOOST_ACCUMULATORS_DEFINE_EXTRACTOR_FUN_IMPL( \ | |
| z \ | |
| , n \ | |
| , BOOST_PP_ARRAY_ELEM(0, _) \ | |
| , BOOST_PP_ARRAY_ELEM(1, _) \ | |
| , BOOST_PP_ARRAY_ELEM(2, _) \ | |
| ) | |
| #define BOOST_ACCUMULATORS_DEFINE_EXTRACTOR(Tag, Feature, ParamSeq) \ | |
| BOOST_PP_REPEAT( \ | |
| BOOST_PP_INC(BOOST_ACCUMULATORS_MAX_ARGS) \ | |
| , BOOST_ACCUMULATORS_DEFINE_EXTRACTOR_FUN \ | |
| , (3, (Tag, Feature, ParamSeq)) \ | |
| ) | |
| }} // namespace boost::accumulators | |
| #endif |