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5天前关闭。
如下例所示，我希望编译器添加一个隐式移动构造函数，将obj1中的数据移动到obj2中，并使obj1为空或具有一些不确定状态。

#include <iostream>
#include <memory>
#include <mutex>
using namespace std;

class Demo
{
public:
    int val = 3;
};

int main()
{
    Demo obj1;
    cout << "before move obj1.val :" << obj1.val << std::endl;
    Demo obj2(std::move(obj1));
    //Expecting obj1.val moves into obj2.val and becomes zero etc.
    cout << "after move obj1.val :" << obj1.val << std::endl; 
    cout << "after move obj2.val :" << obj2.val << std::endl;
    return 0;
}

//输出：

before move obj1.val :3
after move obj1.val :3
after move obj2.val :3