auto_ptr作为函数参数
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#include "stdafx.h"
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#include <iostream>
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#include <memory>
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using namespace std;
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template <class T>
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ostream& operator<< (ostream& os, const auto_ptr<T> &p)
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{
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if(p.get() == NULL)
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os<<"NULL";
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else
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os<< *p;
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return os;
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}
如果不用引用,在函数传参的时候会将指针的控制权交给函数的参数,之后程序就会出问题。![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
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如果不用const,还没想出会有什么后果。
使用auto_ptr需注意的地方:
1 它不能用作数组或容器的对象。
2 它不能进行一般意义的赋值和复制。
3 它的指针算数没有意义。
4 你最好不要用它来传递参数,当不得不用的时候必须用const引用才行。
5 同时不能有两个以上的auto_ptr指向同一个值。
参考:
http://blog.csdn.net/vagrxie/archive/2007/10/12/1821091.aspx