| // Copyright David Abrahams, Daniel Wallin 2003. |
| // 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_PARAMETER_AUX_PACK_DEDUCE_TAG_HPP |
| #define BOOST_PARAMETER_AUX_PACK_DEDUCE_TAG_HPP |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| template < |
| typename Argument |
| , typename ArgumentPack |
| , typename DeducedArgs |
| , typename UsedArgs |
| , typename TagFn |
| , typename EmitsErrors |
| > |
| struct deduce_tag; |
| }}} // namespace boost::parameter::aux |
| |
| #include <boost/parameter/aux_/lambda_tag.hpp> |
| #include <boost/parameter/config.hpp> |
| #include <boost/mpl/apply_wrap.hpp> |
| #include <boost/mpl/lambda.hpp> |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| template <typename Predicate, typename Argument, typename ArgumentPack> |
| struct deduce_tag_condition_mpl |
| : ::boost::mpl::apply_wrap2< |
| typename ::boost::mpl::lambda< |
| Predicate |
| , ::boost::parameter::aux::lambda_tag |
| >::type |
| , Argument |
| , ArgumentPack |
| > |
| { |
| }; |
| }}} // namespace boost::parameter::aux |
| |
| #include <boost/parameter/aux_/has_nested_template_fn.hpp> |
| #include <boost/mp11/list.hpp> |
| #include <boost/mp11/utility.hpp> |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| template <typename Predicate, typename Argument, typename ArgumentPack> |
| struct deduce_tag_condition_mp11 |
| { |
| using type = ::boost::mp11::mp_apply_q< |
| Predicate |
| , ::boost::mp11::mp_list<Argument,ArgumentPack> |
| >; |
| }; |
| |
| template <typename Predicate, typename Argument, typename ArgumentPack> |
| using deduce_tag_condition = ::boost::mp11::mp_if< |
| ::boost::parameter::aux::has_nested_template_fn<Predicate> |
| , ::boost::parameter::aux |
| ::deduce_tag_condition_mp11<Predicate,Argument,ArgumentPack> |
| , ::boost::parameter::aux |
| ::deduce_tag_condition_mpl<Predicate,Argument,ArgumentPack> |
| >; |
| }}} // namespace boost::parameter::aux |
| |
| #else |
| #include <boost/mpl/bool.hpp> |
| #include <boost/mpl/if.hpp> |
| #include <boost/mpl/eval_if.hpp> |
| #include <boost/mpl/assert.hpp> |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| |
| #include <boost/parameter/aux_/set.hpp> |
| #include <boost/parameter/aux_/pack/tag_type.hpp> |
| #include <boost/parameter/aux_/pack/tag_deduced.hpp> |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| // Helper for deduce_tag<...>, below. |
| template < |
| typename Argument |
| , typename ArgumentPack |
| , typename DeducedArgs |
| , typename UsedArgs |
| , typename TagFn |
| , typename EmitsErrors |
| > |
| class deduce_tag0 |
| { |
| typedef typename DeducedArgs::spec _spec; |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| typedef typename ::boost::parameter::aux::deduce_tag_condition< |
| typename _spec::predicate |
| #else |
| typedef typename ::boost::mpl::apply_wrap2< |
| typename ::boost::mpl::lambda< |
| typename _spec::predicate |
| , ::boost::parameter::aux::lambda_tag |
| >::type |
| #endif |
| , Argument |
| , ArgumentPack |
| >::type _condition; |
| |
| #if !defined(BOOST_PARAMETER_CAN_USE_MP11) |
| // Deduced parameter matches several arguments. |
| BOOST_MPL_ASSERT(( |
| typename ::boost::mpl::eval_if< |
| typename ::boost::parameter::aux::has_key_< |
| UsedArgs |
| , typename ::boost::parameter::aux::tag_type<_spec>::type |
| >::type |
| , ::boost::mpl::eval_if< |
| _condition |
| , ::boost::mpl::if_< |
| EmitsErrors |
| , ::boost::mpl::false_ |
| , ::boost::mpl::true_ |
| > |
| , ::boost::mpl::true_ |
| > |
| , ::boost::mpl::true_ |
| >::type |
| )); |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| |
| public: |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| using type = typename ::boost::mp11::mp_if< |
| #else |
| typedef typename ::boost::mpl::eval_if< |
| #endif |
| _condition |
| , ::boost::parameter::aux |
| ::tag_deduced<UsedArgs,_spec,Argument,TagFn> |
| , ::boost::parameter::aux::deduce_tag< |
| Argument |
| , ArgumentPack |
| , typename DeducedArgs::tail |
| , UsedArgs |
| , TagFn |
| , EmitsErrors |
| > |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| >::type; |
| #else |
| >::type type; |
| #endif |
| }; |
| }}} // namespace boost::parameter::aux |
| |
| #include <boost/parameter/aux_/void.hpp> |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| #include <type_traits> |
| #else |
| #include <boost/mpl/pair.hpp> |
| #include <boost/type_traits/is_same.hpp> |
| #endif |
| |
| namespace boost { namespace parameter { namespace aux { |
| |
| // Tries to deduced a keyword tag for a given Argument. |
| // Returns an mpl::pair<> consisting of the tagged_argument<>, |
| // and an mpl::set<> where the new tag has been inserted. |
| // |
| // Argument: The argument type to be tagged. |
| // |
| // ArgumentPack: The ArgumentPack built so far. |
| // |
| // DeducedArgs: A specialization of deduced_item<> (see below). |
| // A list containing only the deduced ParameterSpecs. |
| // |
| // UsedArgs: An mpl::set<> containing the keyword tags used so far. |
| // |
| // TagFn: A metafunction class used to tag positional or deduced |
| // arguments with a keyword tag. |
| template < |
| typename Argument |
| , typename ArgumentPack |
| , typename DeducedArgs |
| , typename UsedArgs |
| , typename TagFn |
| , typename EmitsErrors |
| > |
| struct deduce_tag |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| : ::boost::mp11::mp_if< |
| ::std::is_same<DeducedArgs,::boost::parameter::void_> |
| , ::boost::mp11::mp_identity< |
| ::boost::mp11::mp_list< ::boost::parameter::void_,UsedArgs> |
| > |
| #else |
| : ::boost::mpl::eval_if< |
| ::boost::is_same<DeducedArgs,::boost::parameter::void_> |
| , ::boost::mpl::pair< ::boost::parameter::void_,UsedArgs> |
| #endif |
| , ::boost::parameter::aux::deduce_tag0< |
| Argument |
| , ArgumentPack |
| , DeducedArgs |
| , UsedArgs |
| , TagFn |
| , EmitsErrors |
| > |
| > |
| { |
| }; |
| }}} // namespace boost::parameter::aux |
| |
| #endif // include guard |
| |
