| // Boost.TypeErasure library |
| // |
| // Copyright 2011 Steven Watanabe |
| // |
| // 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) |
| // |
| // $Id$ |
| |
| #if !defined(BOOST_PP_IS_ITERATING) |
| |
| #ifndef BOOST_TYPE_ERASURE_CONSTRUCTIBLE_HPP_INCLUDED |
| #define BOOST_TYPE_ERASURE_CONSTRUCTIBLE_HPP_INCLUDED |
| |
| #include <boost/detail/workaround.hpp> |
| #include <boost/preprocessor/iteration/iterate.hpp> |
| #include <boost/preprocessor/repetition/enum_params.hpp> |
| #include <boost/preprocessor/repetition/enum_binary_params.hpp> |
| #include <boost/preprocessor/repetition/enum_trailing_params.hpp> |
| #include <boost/type_erasure/detail/storage.hpp> |
| #include <boost/type_erasure/call.hpp> |
| #include <boost/type_erasure/concept_interface.hpp> |
| #include <boost/type_erasure/config.hpp> |
| #include <boost/type_erasure/param.hpp> |
| |
| namespace boost { |
| namespace type_erasure { |
| |
| template<class Sig> |
| struct constructible; |
| |
| namespace detail { |
| |
| template<class Sig> |
| struct null_construct; |
| |
| template<class C> |
| struct get_null_vtable_entry; |
| |
| template<class C, class Sig> |
| struct vtable_adapter; |
| |
| }; |
| |
| #ifdef BOOST_TYPE_ERASURE_DOXYGEN |
| |
| /** |
| * The @ref constructible concept enables calling the |
| * constructor of a type contained by an @ref any. |
| * @c Sig should be a function signature. The return |
| * type is the placeholder specifying the type to |
| * be constructed. The arguments are the argument |
| * types of the constructor. The arguments of |
| * @c Sig may be placeholders. |
| * |
| * \note @ref constructible may not be specialized and |
| * may not be passed to \call as it depends on the |
| * implementation details of @ref any. |
| */ |
| template<class Sig> |
| struct constructible {}; |
| |
| #elif !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \ |
| !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \ |
| !BOOST_WORKAROUND(BOOST_MSVC, == 1800) |
| |
| template<class R, class... T> |
| struct constructible<R(T...)> |
| { |
| static ::boost::type_erasure::detail::storage |
| apply(T... arg) |
| { |
| ::boost::type_erasure::detail::storage result; |
| result.data = new R(::std::forward<T>(arg)...); |
| return result; |
| } |
| }; |
| |
| /// INTERNAL ONLY |
| template<class Base, class Tag, class... T> |
| struct concept_interface< |
| ::boost::type_erasure::constructible<Tag(T...)>, |
| Base, |
| Tag |
| > : Base |
| { |
| using Base::_boost_type_erasure_deduce_constructor; |
| ::boost::type_erasure::constructible<Tag(T...)>* |
| _boost_type_erasure_deduce_constructor( |
| typename ::boost::type_erasure::as_param<Base, T>::type...) |
| { |
| return 0; |
| } |
| }; |
| |
| namespace detail { |
| |
| template<class... T> |
| struct null_construct<void(T...)> |
| { |
| static ::boost::type_erasure::detail::storage |
| value(T...) |
| { |
| ::boost::type_erasure::detail::storage result; |
| result.data = 0; |
| return result; |
| } |
| }; |
| |
| template<class T, class R, class... U> |
| struct get_null_vtable_entry<vtable_adapter<constructible<T(const T&)>, R(U...)> > |
| { |
| typedef null_construct<void(U...)> type; |
| }; |
| |
| } |
| |
| #else |
| |
| #define BOOST_PP_FILENAME_1 <boost/type_erasure/constructible.hpp> |
| #define BOOST_PP_ITERATION_LIMITS (0, BOOST_TYPE_ERASURE_MAX_ARITY) |
| #include BOOST_PP_ITERATE() |
| |
| #endif |
| |
| } |
| } |
| |
| #endif |
| |
| #else |
| |
| #define N BOOST_PP_ITERATION() |
| |
| #define BOOST_TYPE_ERASURE_ARG_DECL(z, n, data) \ |
| typename ::boost::type_erasure::as_param< \ |
| Base, \ |
| BOOST_PP_CAT(T, n) \ |
| >::type |
| |
| #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES |
| #define BOOST_TYPE_ERASURE_FORWARD_I(z, n, data) ::std::forward<BOOST_PP_CAT(T, n)>(BOOST_PP_CAT(arg, n)) |
| #define BOOST_TYPE_ERASURE_FORWARD(n) BOOST_PP_ENUM(n, BOOST_TYPE_ERASURE_FORWARD_I, ~) |
| #else |
| #define BOOST_TYPE_ERASURE_FORWARD(n) BOOST_PP_ENUM_PARAMS(n, arg) |
| #endif |
| |
| template<class R BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)> |
| struct constructible<R(BOOST_PP_ENUM_PARAMS(N, T))> |
| { |
| static ::boost::type_erasure::detail::storage |
| apply(BOOST_PP_ENUM_BINARY_PARAMS(N, T, arg)) |
| { |
| ::boost::type_erasure::detail::storage result; |
| result.data = new R(BOOST_TYPE_ERASURE_FORWARD(N)); |
| return result; |
| } |
| }; |
| |
| template<class Base BOOST_PP_ENUM_TRAILING_PARAMS(N, class T), class Tag> |
| struct concept_interface< |
| ::boost::type_erasure::constructible<Tag(BOOST_PP_ENUM_PARAMS(N, T))>, |
| Base, |
| Tag |
| > : Base |
| { |
| using Base::_boost_type_erasure_deduce_constructor; |
| ::boost::type_erasure::constructible<Tag(BOOST_PP_ENUM_PARAMS(N, T))>* |
| _boost_type_erasure_deduce_constructor( |
| BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_ARG_DECL, ~)) |
| { |
| return 0; |
| } |
| }; |
| |
| namespace detail { |
| |
| template<BOOST_PP_ENUM_PARAMS(N, class T)> |
| struct null_construct<void(BOOST_PP_ENUM_PARAMS(N, T))> |
| { |
| static ::boost::type_erasure::detail::storage |
| value(BOOST_PP_ENUM_PARAMS(N, T)) |
| { |
| ::boost::type_erasure::detail::storage result; |
| result.data = 0; |
| return result; |
| } |
| }; |
| |
| template<class T, class R BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)> |
| struct get_null_vtable_entry<vtable_adapter<constructible<T(const T&)>, R(BOOST_PP_ENUM_PARAMS(N, T))> > |
| { |
| typedef null_construct<void(BOOST_PP_ENUM_PARAMS(N, T))> type; |
| }; |
| |
| } |
| |
| #undef BOOST_TYPE_ERASURE_FORWARD |
| #undef BOOST_TYPE_ERASURE_FORWARD_I |
| |
| #undef BOOST_TYPE_ERASURE_ARG_DECL |
| #undef N |
| |
| #endif |