std::return_temporary_buffer

 

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定义于头文件 <memory>
template< class T > void return_temporary_buffer( T* p );		(C++17 中弃用) (C++20 中移除)

解分配先前以 std::get_temporary_buffer 分配的存储。

参数

p

-

指向先前由 std::get_temporary_buffer 分配的存储，且未被之前到 return_temporary_buffer 的调用非法化的指针

返回值

（无）

异常

不抛出。

示例

运行此代码

#include <algorithm>
#include <iostream>
#include <memory>
#include <string>
#include <iterator>
 
int main()
{
    const std::string s[] = {"string", "1", "test", "..."};
    const auto p = std::get_temporary_buffer<std::string>(4);
    // 要求将 p.first 传递给 return_temporary_buffer
    // （当心提前退出和异常）
 
    std::copy(s, s + p.second,
              std::raw_storage_iterator<std::string*, std::string>(p.first));
    // 要求单独销毁每个 p 中的 string
    // （当心提前退出和异常）
 
    std::copy(p.first, p.first + p.second,
              std::ostream_iterator<std::string>{std::cout, "\n"});
 
    std::for_each(p.first, p.first + p.second, [](std::string& e) {
        e.~basic_string<char>();
    });
 
    std::return_temporary_buffer(p.first);
}

输出：

string
1
test
...

参阅

get_temporary_buffer (C++17 中弃用)(C++20 中移除)

获得未初始化存储 (函数模板)