std::make_obj_using_allocator

 

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通用实用程序 日期和时间 函数对象 格式化库 (C++20) bitset hash (C++11) 关系运算符 (C++20 中已弃用) rel_ops::operator!=rel_ops::operator>     rel_ops::operator<=rel_ops::operator>= 整数比较函数 cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) 交换 和 类型操作 swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) 通用词汇类型 pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) 基本字符串转换 to_chars (C++17) from_chars (C++17) chars_format (C++17) to_chars_result (C++17) from_chars_result (C++17)

 

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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) 低级内存 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 其他 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

 

定义在头文件 <memory> 中
template< class T, class Alloc, class... Args > constexpr T make_obj_using_allocator( const Alloc& alloc, Args&&... args );		(自 C++20 起)

通过 使用分配器构造 创建给定类型 T 的对象。

等效于

return std::make_from_tuple<T>(
    std::uses_allocator_construction_args<T>(alloc, std::forward<Args>(args)...)
);

参数

alloc	-	要使用的分配器
args	-	要传递给 T 的构造函数的参数

返回值

新创建的类型为 T 的对象。

异常

可能会抛出 T 的构造函数抛出的任何异常，通常包括 std::bad_alloc。

另请参阅

uses_allocator_construction_args (C++20)	准备与给定类型所需的分配器构造方法匹配的参数列表 (函数模板)
uninitialized_construct_using_allocator (C++20)	通过使用分配器构造在指定内存位置创建给定类型的对象 (函数模板)