boost_mirror/core
1
0
Fork 0
mirror of https://github.com/boostorg/core.git synced 2025-05-09 23:03:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fix MSVC issue with deriving from empty_value

Browse Source
This commit is contained in:
Braden Ganetsky 2024-07-11 17:02:21 -05:00
parent c056f3dfc9
commit e22bd49fa7
1 changed files with 49 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

54
include/boost/core/empty_value.hpp
View File

@ -95,9 +95,53 @@ private:
};
#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
#if defined(BOOST_MSVC)
namespace detail {
template<class T>
class empty_value_base
: public T {
public:
#if !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS)
empty_value_base() = default;
#else
BOOST_CONSTEXPR empty_value_base() { }
#endif
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
template<class U, class... Args>
BOOST_CONSTEXPR empty_value_base(U&& value, Args&&... args)
: T(std::forward<U>(value), std::forward<Args>(args)...) { }
#else
template<class U>
BOOST_CONSTEXPR empty_value_base(U&& value)
: T(std::forward<U>(value)) { }
#endif
#else
template<class U>
BOOST_CONSTEXPR empty_value_base(const U& value)
: T(value) { }
template<class U>
BOOST_CONSTEXPR empty_value_base(U& value)
: T(value) { }
#endif
};
} /* detail */
#endif
template<class T, unsigned N>
class empty_value<T, N, true>
#if defined(BOOST_MSVC)
: detail::empty_value_base<T> {
typedef detail::empty_value_base<T> base;
#else
: T {
typedef T base;
#endif
public:
typedef T type;
@ -108,26 +152,26 @@ public:
#endif
BOOST_CONSTEXPR empty_value(boost::empty_init_t)
: T() { }
: base() { }
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
template<class U, class... Args>
BOOST_CONSTEXPR empty_value(boost::empty_init_t, U&& value, Args&&... args)
: T(std::forward<U>(value), std::forward<Args>(args)...) { }
: base(std::forward<U>(value), std::forward<Args>(args)...) { }
#else
template<class U>
BOOST_CONSTEXPR empty_value(boost::empty_init_t, U&& value)
: T(std::forward<U>(value)) { }
: base(std::forward<U>(value)) { }
#endif
#else
template<class U>
BOOST_CONSTEXPR empty_value(boost::empty_init_t, const U& value)
: T(value) { }
: base(value) { }
template<class U>
BOOST_CONSTEXPR empty_value(boost::empty_init_t, U& value)
: T(value) { }
: base(value) { }
#endif
BOOST_CONSTEXPR const T& get() const BOOST_NOEXCEPT {