swap(std::jthread)

 

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std::jthread

成员函数

jthread::jthread

jthread::~jthread

jthread::operator=

观察器

jthread::joinable

jthread::get_id

jthread::native_handle

jthread::hardware_concurrency

操作

jthread::join

jthread::detach

jthread::swap

停止状态处理

jthread::get_stop_source

jthread::get_stop_token

jthread::request_stop

非成员函数

swap(std::jthread)

 

friend void swap( jthread &lhs, jthread &rhs ) noexcept;		(C++20 起)

对 std::jthread 重载 std::swap 算法。交换 lhs 与 rhs 的状态。等效地调用 lhs.swap(rhs) 。此函数对通常无限定或有限定查找不可见，而只能在 std::jthread 为参数的关联类时由实参依赖查找找到。

参数

lhs, rhs

-

要交换状态的 jthread

返回值

（无）

示例

运行此代码

#include <iostream>
#include <thread>
#include <chrono>
 
void foo()
{
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
void bar()
{
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
int main()
{
    using std::swap;
 
    std::jthread t1(foo);
    std::jthread t2(bar);
 
    std::cout << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
    swap(t1, t2);
 
    std::cout << "after std::swap(t1, t2):" << '\n'
              << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
    t1.swap(t2);
 
    std::cout << "after t1.swap(t2):" << '\n'
              << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
 
}

可能的输出：

thread 1 id: 1892
thread 2 id: 2584
after std::swap(t1, t2):
thread 1 id: 2584
thread 2 id: 1892
after t1.swap(t2):
thread 1 id: 1892
thread 2 id: 2584

参阅

swap	交换二个 jthread 对象 (公开成员函数)