diff options
Diffstat (limited to 'boost/type_erasure/detail/extract_concept.hpp')
| -rw-r--r-- | boost/type_erasure/detail/extract_concept.hpp | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/boost/type_erasure/detail/extract_concept.hpp b/boost/type_erasure/detail/extract_concept.hpp index f519045d6c..0b1ce5d2fa 100644 --- a/boost/type_erasure/detail/extract_concept.hpp +++ b/boost/type_erasure/detail/extract_concept.hpp @@ -42,6 +42,33 @@ struct combine_concepts<void, T> { typedef T type; }; template<> struct combine_concepts<void, void> { typedef void type; }; +#ifdef BOOST_TYPE_ERASURE_USE_MP11 + +template<class T, class U> +using combine_concepts_t = typename ::boost::type_erasure::detail::combine_concepts<T, U>::type; + +template<class T, class U> +using extract_concept_or_void = + ::boost::mp11::mp_eval_if_c< + !::boost::type_erasure::is_placeholder< + ::boost::remove_cv_t< + ::boost::remove_reference_t<T> + > + >::value, + void, + ::boost::type_erasure::concept_of_t, U + >; + +template<class L1, class L2> +using extract_concept_t = + ::boost::mp11::mp_fold< + ::boost::mp11::mp_transform< ::boost::type_erasure::detail::extract_concept_or_void, L1, L2>, + void, + ::boost::type_erasure::detail::combine_concepts_t + >; + +#else + template<class T, class U> struct maybe_extract_concept { @@ -56,7 +83,7 @@ struct maybe_extract_concept >::type type; }; -#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) +#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) template<class Args, class... U> struct extract_concept; @@ -82,7 +109,6 @@ struct extract_concept<void()> }; #else -//#endif #define BOOST_PP_FILENAME_1 <boost/type_erasure/detail/extract_concept.hpp> #define BOOST_PP_ITERATION_LIMITS (1, BOOST_TYPE_ERASURE_MAX_ARITY) @@ -90,6 +116,8 @@ struct extract_concept<void()> #endif +#endif + } } } |