| // Copyright David Abrahams 2005. |
| // 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_BINDING_DWA200558_HPP |
| #define BOOST_PARAMETER_BINDING_DWA200558_HPP |
| |
| #include <boost/parameter/aux_/void.hpp> |
| #include <boost/parameter/config.hpp> |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| #include <boost/mp11/integral.hpp> |
| #include <boost/mp11/list.hpp> |
| #include <boost/mp11/utility.hpp> |
| #include <type_traits> |
| #else |
| #include <boost/mpl/bool.hpp> |
| #include <boost/mpl/if.hpp> |
| #include <boost/mpl/eval_if.hpp> |
| #include <boost/mpl/identity.hpp> |
| #include <boost/mpl/apply_wrap.hpp> |
| #include <boost/mpl/assert.hpp> |
| #include <boost/type_traits/is_same.hpp> |
| #endif |
| |
| namespace boost { namespace parameter { |
| |
| // A metafunction that, given an argument pack, returns the reference type |
| // of the parameter identified by the given keyword. If no such parameter |
| // has been specified, returns Default |
| |
| template <typename Parameters, typename Keyword, typename Default> |
| struct binding0 |
| { |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| using type = ::boost::mp11::mp_apply_q< |
| typename Parameters::binding |
| , ::boost::mp11::mp_list<Keyword,Default,::boost::mp11::mp_true> |
| >; |
| |
| static_assert( |
| ::boost::mp11::mp_if< |
| ::std::is_same<Default,::boost::parameter::void_> |
| , ::boost::mp11::mp_if< |
| ::std::is_same<type,::boost::parameter::void_> |
| , ::boost::mp11::mp_false |
| , ::boost::mp11::mp_true |
| > |
| , ::boost::mp11::mp_true |
| >::value |
| , "required parameters must not result in void_ type" |
| ); |
| #else // !defined(BOOST_PARAMETER_CAN_USE_MP11) |
| typedef typename ::boost::mpl::apply_wrap3< |
| typename Parameters::binding |
| , Keyword |
| , Default |
| , ::boost::mpl::true_ |
| >::type type; |
| |
| BOOST_MPL_ASSERT(( |
| typename ::boost::mpl::eval_if< |
| ::boost::is_same<Default,::boost::parameter::void_> |
| , ::boost::mpl::if_< |
| ::boost::is_same<type,::boost::parameter::void_> |
| , ::boost::mpl::false_ |
| , ::boost::mpl::true_ |
| > |
| , ::boost::mpl::true_ |
| >::type |
| )); |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| }; |
| |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| template <typename Placeholder, typename Keyword, typename Default> |
| struct binding1 |
| { |
| using type = ::boost::mp11::mp_apply_q< |
| Placeholder |
| , ::boost::mp11::mp_list<Keyword,Default,::boost::mp11::mp_true> |
| >; |
| |
| static_assert( |
| ::boost::mp11::mp_if< |
| ::std::is_same<Default,::boost::parameter::void_> |
| , ::boost::mp11::mp_if< |
| ::std::is_same<type,::boost::parameter::void_> |
| , ::boost::mp11::mp_false |
| , ::boost::mp11::mp_true |
| > |
| , ::boost::mp11::mp_true |
| >::value |
| , "required parameters must not result in void_ type" |
| ); |
| }; |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| }} // namespace boost::parameter |
| |
| #include <boost/parameter/aux_/is_placeholder.hpp> |
| |
| namespace boost { namespace parameter { |
| |
| template < |
| typename Parameters |
| , typename Keyword |
| , typename Default = ::boost::parameter::void_ |
| > |
| struct binding |
| #if !defined(BOOST_PARAMETER_CAN_USE_MP11) |
| : ::boost::mpl::eval_if< |
| ::boost::parameter::aux::is_mpl_placeholder<Parameters> |
| , ::boost::mpl::identity<int> |
| , ::boost::parameter::binding0<Parameters,Keyword,Default> |
| > |
| #endif |
| { |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| using type = typename ::boost::mp11::mp_if< |
| ::boost::parameter::aux::is_mpl_placeholder<Parameters> |
| , ::boost::mp11::mp_identity<int> |
| , ::boost::mp11::mp_if< |
| ::boost::parameter::aux::is_mp11_placeholder<Parameters> |
| , ::boost::parameter::binding1<Parameters,Keyword,Default> |
| , ::boost::parameter::binding0<Parameters,Keyword,Default> |
| > |
| >::type; |
| #endif |
| }; |
| }} // namespace boost::parameter |
| |
| #include <boost/parameter/aux_/result_of0.hpp> |
| |
| namespace boost { namespace parameter { |
| |
| // A metafunction that, given an argument pack, returns the reference type |
| // of the parameter identified by the given keyword. If no such parameter |
| // has been specified, returns the type returned by invoking DefaultFn |
| template <typename Parameters, typename Keyword, typename DefaultFn> |
| struct lazy_binding |
| { |
| #if defined(BOOST_PARAMETER_CAN_USE_MP11) |
| using type = ::boost::mp11::mp_apply_q< |
| typename Parameters::binding |
| , ::boost::mp11::mp_list< |
| Keyword |
| , typename ::boost::parameter::aux::result_of0<DefaultFn>::type |
| , ::boost::mp11::mp_true |
| > |
| >; |
| #else |
| typedef typename ::boost::mpl::apply_wrap3< |
| typename Parameters::binding |
| , Keyword |
| , typename ::boost::parameter::aux::result_of0<DefaultFn>::type |
| , ::boost::mpl::true_ |
| >::type type; |
| #endif // BOOST_PARAMETER_CAN_USE_MP11 |
| }; |
| }} // namespace boost::parameter |
| |
| #endif // include guard |
| |