模板类的友元重载（<>）

//============================================================================
// Name        : templatefriend.cpp
// Author      : 
// Version     :
// Copyright   : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <iostream>
using namespace std;

template <class T>  //前向声明
class Test;
template <class T>
ostream & operator<<(ostream &out,const Test<T> &obj);


template <class T>
Test<T> operator+(const Test<T> &obj,const Test<T> &obj1);

template <class T>
class Test
{
public:
	Test(int n=0){num = n;}
	Test(const Test<T>©) {num = copy.num;}
	friend ostream & operator << <>(ostream &out, const Test<T>&obj);
	friend Test<T> operator+ <>(const Test<T> &obj,const Test<T> &obj1);
private:
	int num;
};


template <class T>
ostream& operator<<(ostream & out, const Test<T>&obj)
{
	out<<obj.num;
	return out;
}
template <class T>
Test<T> operator+(const Test<T> &obj,const Test<T> &obj1)
{
	Test<T>  temp;
	temp = obj.num + obj1.num;
	return temp;
}


int main()
{
	Test<int> t(2);
	cout<<t;
	return 0;
}