std::get_pointer_safety

 

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语言支持 类型支持（基本类型、 RTTI） 库功能特性测试宏 (C++20) 动态内存管理 程序工具 协程支持 (C++20) 变参数函数 is_constant_evaluated (C++20) is_within_lifetime (C++26) initializer_list (C++11) source_location (C++20) 三路比较 (C++20) three_way_comparablethree_way_comparable_with (C++20)(C++20) strong_ordering (C++20) weak_ordering (C++20) partial_ordering (C++20) common_comparison_category (C++20) compare_three_way_result (C++20) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20) is_eqis_neqis_ltis_lteqis_gtis_gteq (C++20)(C++20)(C++20)(C++20)(C++20)(C++20)

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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) 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 set_new_handler launder (C++17) bad_alloc bad_array_new_length nothrow_t align_val_t destroying_delete_t 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

 

在标头 <memory> 定义
std::pointer_safety get_pointer_safety() noexcept;		(C++11 起) (C++23 中移除)

获得实现定义的指针安全模式，它是 std::pointer_safety 类型的值。

参数

（无）

返回值

此实现所用的 pointer_safety 。

示例

运行此代码

#include <iostream>
#include <memory>
 
int main()
{
    std::cout << "Pointer safety: ";
    switch (std::get_pointer_safety()) {
        case std::pointer_safety::strict:    std::cout << "strict\n"; break;
        case std::pointer_safety::preferred: std::cout << "preferred\n"; break;
        case std::pointer_safety::relaxed:   std::cout << "relaxed\n"; break;
    }
}

可能的输出：

Pointer safety: relaxed

参阅

pointer_safety (C++11)(C++23 中移除)

列出指针安全模式 (枚举)