学步园

一开始还发现这货挺方便的.后来才发现还是不行,

多引用时,就会重复删除了

 

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


void func(const auto_ptr<int>& pInt)
{
    cout << *pInt<<endl;
}

class X
{
public:
    X(){cout <<"construct"<<endl;}
    ~ X(){cout <<"destructor"<<endl;}
};

int main()
{
#if 0
    auto_ptr<int> a(new int(100));
    func(a);
#endif


    //error use begin
     X* x = new X;
    auto_ptr<X> p1(x);

    delete x;        //destructor 1

    //error use begin
    return 0;
}
    //destructor 2

#if 0  //normal use


int main()
{
    cout <<"before scope"<<endl;
    {
    auto_ptr<X> p1(new X);
    cout <<"I will exit the scope" <<endl;

    }
    cout <<"after scope"<<endl;

    cout <<"------------------------------"<<endl;
    cout <<"before scope"<<endl;
    {
    auto_ptr<X> p1(new X);
    delete p1;;
    cout <<"I will exit the scope" <<endl;

    }
    cout <<"after scope"<<endl;
    return 0;
}
#endif //normal use