std::get_temporary_buffer

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C++
 
实用工具库
类型的支持 (basic types, RTTI, type traits)
动态内存管理
错误处理
程序实用工具
可变参数函数
日期和时间
函数对象
initializer_list（C++11）
bitset
hash（C++11）
关系运算符
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Relational operators
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rel_ops::operator!=
rel_ops::operator>
rel_ops::operator<=
rel_ops::operator>=
双和元组
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Pairs and tuples
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pair
tuple（C++11）
piecewise_construct_t（C++11）
piecewise_construct（C++11）
掉期，远期和移动
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Swap, forward and move
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swap
forward（C++11）
move（C++11）
move_if_noexcept（C++11）
declval（C++11）
 
动态内存管理
低级别的内存管理
分配器
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Allocators
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allocator
allocator_traits（C++11）
allocator_arg_t（C++11）
allocator_arg（C++11）
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未初始化的存储空间
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Uninitialized storage
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uninitialized_copy
uninitialized_copy_n（C++11）
uninitialized_fill
uninitialized_fill_n
raw_storage_iterator
get_temporary_buffer
return_temporary_buffer
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Smart pointers
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Garbage collection support
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Miscellaneous
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pointer_traits（C++11）
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C库
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C Library
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Defined in header <memory>
template< class T >
std::pair< T*, std::ptrdiff_t > get_temporary_buffer( std::ptrdiff_t count )
分配存储空间，足够存储多达count相邻对象的类型T。如果没有足够的内存为所有count对象，分配不到count，如果可能的话.
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Allocates storage sufficient to store up to count adjacent objects of type T. If there is insufficient memory for all count objects, allocates less than count, if possible.
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目录

[编辑] 参数

count -
要分配的对象的数量
Original:
the number of objects to allocate
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[编辑] 返回值

一种std::pair保持一个指针到已分配的存储的开始和适合实际分配的存储在存储对象的数目（可能为零）.
Original:
An std::pair holding a pointer to the beginning of the allocated storage and the number of objects that fit in the storage that was actually allocated (may be zero).
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[编辑] 例外

noexcept specification:  
noexcept
  （C++11 起）

[编辑] 为例

[edit]
#include <algorithm>
#include <iostream>
#include <memory>
#include <string>
 
int main()
{
    const std::string s[] = {"string", "1", "test", "..."};
    std::string* p = std::get_temporary_buffer<std::string>(4).first;
 
    std::copy(std::begin(s), std::end(s),
              std::raw_storage_iterator<std::string*, std::string>(p));
 
    for (std::string* i = p; i != p+4; ++i) {
        std::cout << *i << '\n';
        i->~basic_string<char>();
    }
    std::return_temporary_buffer(p);
}

Output: 

string
1
test
...

[编辑] 另请参阅
释放未初始化的存储
Original:
frees uninitialized storage
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（函数模板） [edit]
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/memory/get_temporary_buffer&oldid=27356”