std::shared_ptr<T>::owner_hash

 

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智能指针 unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (直到 C++17*) 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) 底层内存 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) is_sufficiently_aligned (C++26)

 

std::shared_ptr

成员函数

shared_ptr::shared_ptr

shared_ptr::~shared_ptr

shared_ptr::operator=

修改器

shared_ptr::reset

shared_ptr::swap

观察器

shared_ptr::get

shared_ptr::operator*shared_ptr::operator->

shared_ptr::operator[] (C++17)

shared_ptr::use_count

shared_ptr::unique (直到 C++20*)

shared_ptr::operator bool

shared_ptr::owner_before

shared_ptr::owner_hash (C++26)

shared_ptr::owner_equal (C++26)

非成员函数

swap(std::shared_ptr)

make_sharedmake_shared_for_overwrite (C++20)

allocate_sharedallocate_shared_for_overwrite (C++20)

static_pointer_castdynamic_pointer_castconst_pointer_castreinterpret_pointer_cast (C++17)

get_deleter

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

operator<<

atomic_xxx 函数 (直到 C++26*)

辅助类

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

hash<std::shared_ptr>

推导指引(C++17)

 

std::size_t owner_hash() const noexcept;		(自 C++26 起)

返回一个未指定的值，使得对于任何对象 other，当 owner_equal(other) 为 true 时，owner_hash() == other.owner_hash() 也为 true。

此哈希用于使 shared 和 weak 指针可以用作无序关联容器中的键，通常通过 std::owner_hash。

返回值

对于任何共享相同所有权的 std::shared_ptr 或 std::weak_ptr 对象，此函数返回的值都相同。

注解

特性测试 宏	值	Std	特性
__cpp_lib_smart_ptr_owner_equality	202306L	(C++26)	启用 std::shared_ptr 作为 无序关联容器 中键的使用

参见

owner_hash (C++26)

为 shared 和 weak 指针提供基于所有者的哈希 (类)