std::pmr::null_memory_resource

 

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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_resource> 定义
std::pmr::memory_resource* null_memory_resource() noexcept;		(C++17 起)

返回指向不进行任何分配的 memory_resource 的指针。

返回值

返回指针 p ，指向导出自 std::pmr::memory_resource 类型的静态存储期对象，它拥有下列属性：

• 其 allocate() 函数始终抛出 std::bad_alloc ；
• 其 deallocate() 函数无效果；
• 对于任何 memory_resource r ， p->is_equal(r) 返回 &r == p 。

每次调用此函数都返回相同值。