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- // <experimental/memory> -*- C++ -*-
-
- // Copyright (C) 2015-2020 Free Software Foundation, Inc.
- //
- // This file is part of the GNU ISO C++ Library. This library is free
- // software; you can redistribute it and/or modify it under the
- // terms of the GNU General Public License as published by the
- // Free Software Foundation; either version 3, or (at your option)
- // any later version.
-
- // This library is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
-
- // Under Section 7 of GPL version 3, you are granted additional
- // permissions described in the GCC Runtime Library Exception, version
- // 3.1, as published by the Free Software Foundation.
-
- // You should have received a copy of the GNU General Public License and
- // a copy of the GCC Runtime Library Exception along with this program;
- // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
- // <http://www.gnu.org/licenses/>.
-
- /** @file experimental/memory
- * This is a TS C++ Library header.
- * @ingroup libfund-ts
- */
-
- //
- // N4336 Working Draft, C++ Extensions for Library Fundamentals, Version 2
- //
-
- #ifndef _GLIBCXX_EXPERIMENTAL_MEMORY
- #define _GLIBCXX_EXPERIMENTAL_MEMORY 1
-
- #pragma GCC system_header
-
- #if __cplusplus >= 201402L
-
- #include <memory>
- #include <type_traits>
- #include <utility>
- #include <experimental/bits/shared_ptr.h>
- #include <bits/functional_hash.h>
-
- namespace std _GLIBCXX_VISIBILITY(default)
- {
- _GLIBCXX_BEGIN_NAMESPACE_VERSION
-
- namespace experimental
- {
- inline namespace fundamentals_v2
- {
- #define __cpp_lib_experimental_observer_ptr 201411
-
- template <typename _Tp>
- class observer_ptr
- {
- public:
- // publish our template parameter and variations thereof
- using element_type = _Tp;
- using __pointer = add_pointer_t<_Tp>; // exposition-only
- using __reference = add_lvalue_reference_t<_Tp>; // exposition-only
-
- // 3.2.2, observer_ptr constructors
- // default c'tor
- constexpr observer_ptr() noexcept
- : __t()
- { }
-
- // pointer-accepting c'tors
- constexpr observer_ptr(nullptr_t) noexcept
- : __t()
- { }
-
- constexpr explicit observer_ptr(__pointer __p) noexcept
- : __t(__p)
- { }
-
- // copying c'tors (in addition to compiler-generated copy c'tor)
- template <typename _Up,
- typename = typename enable_if<
- is_convertible<typename add_pointer<_Up>::type, __pointer
- >::value
- >::type>
- constexpr observer_ptr(observer_ptr<_Up> __p) noexcept
- : __t(__p.get())
- {
- }
-
- // 3.2.3, observer_ptr observers
- constexpr __pointer
- get() const noexcept
- {
- return __t;
- }
-
- constexpr __reference
- operator*() const
- {
- return *get();
- }
-
- constexpr __pointer
- operator->() const noexcept
- {
- return get();
- }
-
- constexpr explicit operator bool() const noexcept
- {
- return get() != nullptr;
- }
-
- // 3.2.4, observer_ptr conversions
- constexpr explicit operator __pointer() const noexcept
- {
- return get();
- }
-
- // 3.2.5, observer_ptr modifiers
- constexpr __pointer
- release() noexcept
- {
- __pointer __tmp = get();
- reset();
- return __tmp;
- }
-
- constexpr void
- reset(__pointer __p = nullptr) noexcept
- {
- __t = __p;
- }
-
- constexpr void
- swap(observer_ptr& __p) noexcept
- {
- std::swap(__t, __p.__t);
- }
-
- private:
- __pointer __t;
- }; // observer_ptr<>
-
- template<typename _Tp>
- void
- swap(observer_ptr<_Tp>& __p1, observer_ptr<_Tp>& __p2) noexcept
- {
- __p1.swap(__p2);
- }
-
- template<typename _Tp>
- observer_ptr<_Tp>
- make_observer(_Tp* __p) noexcept
- {
- return observer_ptr<_Tp>(__p);
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator==(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return __p1.get() == __p2.get();
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator!=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return !(__p1 == __p2);
- }
-
- template<typename _Tp>
- bool
- operator==(observer_ptr<_Tp> __p, nullptr_t) noexcept
- {
- return !__p;
- }
-
- template<typename _Tp>
- bool
- operator==(nullptr_t, observer_ptr<_Tp> __p) noexcept
- {
- return !__p;
- }
-
- template<typename _Tp>
- bool
- operator!=(observer_ptr<_Tp> __p, nullptr_t) noexcept
- {
- return bool(__p);
- }
-
- template<typename _Tp>
- bool
- operator!=(nullptr_t, observer_ptr<_Tp> __p) noexcept
- {
- return bool(__p);
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator<(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return std::less<typename common_type<typename add_pointer<_Tp>::type,
- typename add_pointer<_Up>::type
- >::type
- >{}(__p1.get(), __p2.get());
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator>(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return __p2 < __p1;
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator<=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return !(__p2 < __p1);
- }
-
- template<typename _Tp, typename _Up>
- bool
- operator>=(observer_ptr<_Tp> __p1, observer_ptr<_Up> __p2)
- {
- return !(__p1 < __p2);
- }
- } // namespace fundamentals_v2
- } // namespace experimental
-
- template <typename _Tp>
- struct hash<experimental::observer_ptr<_Tp>>
- {
- using result_type = size_t;
- using argument_type = experimental::observer_ptr<_Tp>;
-
- size_t
- operator()(const experimental::observer_ptr<_Tp>& __t) const
- noexcept(noexcept(hash<typename add_pointer<_Tp>::type> {}(__t.get())))
- {
- return hash<typename add_pointer<_Tp>::type> {}(__t.get());
- }
- };
-
-
- _GLIBCXX_END_NAMESPACE_VERSION
- } // namespace std
-
- #endif // __cplusplus <= 201103L
-
- #endif // _GLIBCXX_EXPERIMENTAL_MEMORY
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