std::shared_ptr<T>::owner_equal

 

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智能指针 unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (C++17 前*) owner_less (C++11) owner_less<void> (C++17) owner_hash (C++26) owner_equal (C++26) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (C++23) 低层内存管理 operator new operator new[] operator delete operator delete[] get_new_handler (C++11) set_new_handler launder (C++17) bad_alloc bad_array_new_length (C++11) nothrow_t align_val_t (C++17) destroying_delete_t (C++20) new_handler nothrow 杂项 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C 库 malloc calloc realloc    aligned_alloc (C++17) free

 

std::shared_ptr

成员函数

shared_ptr::shared_ptr

shared_ptr::~shared_ptr

shared_ptr::operator=

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shared_ptr::get

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shared_ptr::unique (C++20 前*)

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shared_ptr::owner_before

shared_ptr::owner_hash (C++26)

shared_ptr::owner_equal (C++26)

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swap(std::shared_ptr)

make_sharedmake_shared_for_overwrite (C++20)

allocate_sharedallocate_shared_for_overwrite (C++20)

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get_deleter

operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20 前)(C++20 前)(C++20 前)(C++20 前)(C++20 前)(C++20)

operator<<

atomic_xxx 函数 (C++26 前*)

辅助类

atomic<std::shared_ptr> (C++20)

hash<std::shared_ptr>

推导指引(C++17)

 

template< class Y > bool owner_equal( const std::shared_ptr<Y>& other ) const noexcept;	(1)	(C++26 起)
template< class Y > bool owner_equal( const std::weak_ptr<Y>& other ) const noexcept;	(2)	(C++26 起)

检查此 shared_ptr 与 other 是否共享所有权或均为空。比较方式使得两个智能指针当且仅当它们均为空或拥有同一对象时比较相等，即使从 get() 获得的指针值不同（例如因为它们指向同一对象的不同子对象）也是如此。

成员函数 owner_equal 是一种等价关系，当且仅当 owner_equal(other) 为 true 时 !owner_before(other) && !other.owner_before(*this) 为 true。

此顺序常通过 std::owner_equal 使用，使得共享指针与弱指针能用作无序关联容器的键。

参数

other

-

要比较的 std::shared_ptr 或 std::weak_ptr

返回值

若 *this 与 other 共享所有权或均为空则为 true。否则返回 false。

注解

功能特性测试宏	值	标准	功能特性
__cpp_lib_smart_ptr_owner_equality	202306L	(C++26)	启用以 std::shared_ptr 为无序关联容器中的键

参阅

owner_equal (C++26)

提供共享指针与弱指针的基于拥有者的混合类型相等比较 (类)