| // (C) Copyright Antony Polukhin 2013. |
| // |
| // Use, modification and distribution are subject to 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). |
| // |
| // See http://www.boost.org/libs/type_traits for most recent version including documentation. |
| |
| #ifndef BOOST_TT_IS_COPY_CONSTRUCTIBLE_HPP_INCLUDED |
| #define BOOST_TT_IS_COPY_CONSTRUCTIBLE_HPP_INCLUDED |
| |
| #include <boost/config.hpp> |
| #include <boost/detail/workaround.hpp> |
| |
| #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_DECLTYPE) && !BOOST_WORKAROUND(BOOST_MSVC, < 1800) && !BOOST_WORKAROUND(BOOST_GCC_VERSION, < 40900) |
| |
| #include <boost/type_traits/is_constructible.hpp> |
| |
| #if !BOOST_WORKAROUND(BOOST_MSVC, <= 1800) |
| |
| namespace boost { |
| |
| template <class T> struct is_copy_constructible : public boost::is_constructible<T, const T&>{}; |
| |
| template <> struct is_copy_constructible<void> : public false_type{}; |
| template <> struct is_copy_constructible<void const> : public false_type{}; |
| template <> struct is_copy_constructible<void const volatile> : public false_type{}; |
| template <> struct is_copy_constructible<void volatile> : public false_type{}; |
| |
| } // namespace boost |
| |
| #else |
| // |
| // Special version for VC12 which has a problem when a base class (such as non_copyable) has a deleted |
| // copy constructor. In this case the compiler thinks there really is a copy-constructor and tries to |
| // instantiate the deleted member. std::is_copy_constructible has the same issue (or at least returns |
| // an incorrect value, which just defers the issue into the users code) as well. We can at least fix |
| // boost::non_copyable as a base class as a special case: |
| // |
| #include <boost/type_traits/is_noncopyable.hpp> |
| |
| namespace boost { |
| |
| namespace detail |
| { |
| |
| template <class T, bool b> struct is_copy_constructible_imp : public boost::is_constructible<T, const T&>{}; |
| template <class T> struct is_copy_constructible_imp<T, true> : public false_type{}; |
| |
| } |
| |
| template <class T> struct is_copy_constructible : public detail::is_copy_constructible_imp<T, is_noncopyable<T>::value>{}; |
| |
| template <> struct is_copy_constructible<void> : public false_type{}; |
| template <> struct is_copy_constructible<void const> : public false_type{}; |
| template <> struct is_copy_constructible<void const volatile> : public false_type{}; |
| template <> struct is_copy_constructible<void volatile> : public false_type{}; |
| |
| } // namespace boost |
| |
| #endif |
| |
| #else |
| |
| #include <boost/type_traits/detail/yes_no_type.hpp> |
| #include <boost/type_traits/is_noncopyable.hpp> |
| #include <boost/type_traits/add_reference.hpp> |
| #include <boost/type_traits/is_rvalue_reference.hpp> |
| #include <boost/type_traits/declval.hpp> |
| #include <boost/type_traits/is_array.hpp> |
| #include <boost/type_traits/declval.hpp> |
| |
| #ifdef BOOST_MSVC |
| #pragma warning(push) |
| #pragma warning(disable:4181) |
| #endif |
| |
| namespace boost { |
| |
| namespace detail{ |
| |
| template <bool DerivedFromNoncopyable, class T> |
| struct is_copy_constructible_impl2 { |
| |
| // Intel compiler has problems with SFINAE for copy constructors and deleted functions: |
| // |
| // error: function *function_name* cannot be referenced -- it is a deleted function |
| // static boost::type_traits::yes_type test(T1&, decltype(T1(boost::declval<T1&>()))* = 0); |
| // ^ |
| // |
| // MSVC 12.0 (Visual 2013) has problems when the copy constructor has been deleted. See: |
| // https://connect.microsoft.com/VisualStudio/feedback/details/800328/std-is-copy-constructible-is-broken |
| #if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) && !defined(BOOST_INTEL_CXX_VERSION) && !(defined(BOOST_MSVC) && _MSC_VER == 1800) |
| |
| #ifdef BOOST_NO_CXX11_DECLTYPE |
| template <class T1> |
| static boost::type_traits::yes_type test(const T1&, boost::mpl::int_<sizeof(T1(boost::declval<const T1&>()))>* = 0); |
| #else |
| template <class T1> |
| static boost::type_traits::yes_type test(const T1&, decltype(T1(boost::declval<const T1&>()))* = 0); |
| #endif |
| |
| static boost::type_traits::no_type test(...); |
| #else |
| template <class T1> |
| static boost::type_traits::no_type test(const T1&, typename T1::boost_move_no_copy_constructor_or_assign* = 0); |
| static boost::type_traits::yes_type test(...); |
| #endif |
| |
| // If you see errors like this: |
| // |
| // `'T::T(const T&)' is private` |
| // `boost/type_traits/is_copy_constructible.hpp:68:5: error: within this context` |
| // |
| // then you are trying to call that macro for a structure defined like that: |
| // |
| // struct T { |
| // ... |
| // private: |
| // T(const T &); |
| // ... |
| // }; |
| // |
| // To fix that you must modify your structure: |
| // |
| // // C++03 and C++11 version |
| // struct T: private boost::noncopyable { |
| // ... |
| // private: |
| // T(const T &); |
| // ... |
| // }; |
| // |
| // // C++11 version |
| // struct T { |
| // ... |
| // private: |
| // T(const T &) = delete; |
| // ... |
| // }; |
| BOOST_STATIC_CONSTANT(bool, value = ( |
| sizeof(test( |
| boost::declval<BOOST_DEDUCED_TYPENAME boost::add_reference<T const>::type>() |
| )) == sizeof(boost::type_traits::yes_type) |
| && |
| !boost::is_rvalue_reference<T>::value |
| && !boost::is_array<T>::value |
| )); |
| }; |
| |
| template <class T> |
| struct is_copy_constructible_impl2<true, T> { |
| BOOST_STATIC_CONSTANT(bool, value = false); |
| }; |
| |
| template <class T> |
| struct is_copy_constructible_impl { |
| |
| BOOST_STATIC_CONSTANT(bool, value = ( |
| boost::detail::is_copy_constructible_impl2< |
| boost::is_noncopyable<T>::value, |
| T |
| >::value |
| )); |
| }; |
| |
| } // namespace detail |
| |
| template <class T> struct is_copy_constructible : public integral_constant<bool, ::boost::detail::is_copy_constructible_impl<T>::value>{}; |
| template <> struct is_copy_constructible<void> : public false_type{}; |
| #ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS |
| template <> struct is_copy_constructible<void const> : public false_type{}; |
| template <> struct is_copy_constructible<void volatile> : public false_type{}; |
| template <> struct is_copy_constructible<void const volatile> : public false_type{}; |
| #endif |
| |
| } // namespace boost |
| |
| #ifdef BOOST_MSVC |
| #pragma warning(pop) |
| #endif |
| |
| #endif |
| |
| #endif // BOOST_TT_IS_COPY_CONSTRUCTIBLE_HPP_INCLUDED |