#include <iostream>
#include <sstream>
#include <string>
using std::cout;
using std::ostream;
//endl是操作算子，LZ可以定义自己的endl覆盖std中的；
ostream & endl(ostream & os)
{
    cout<<"my endl\n";
    return os;
}//在这里面干自己想干的事


void main()
{
    cout<<"test :"<<endl;
}

cout<<"test :"<<endl;
/*一般操纵算子，内部应该是这样实现的：
ostream & ostream::operator<<(ostream &(*pf)(ostream & os)
{
return (*pf)(*this）；
}
所以endl其实是个函数指针*/

#define endl "hello \r\n"


int main(int argc , char* arcv[])
{


    cout<<endl;
    system("pause");
    return EXIT_SUCCESS;
}

class xstream : public ostringstream
{
public:
    // Constructors, etc.
    // ........
    inline xstream& endl( xstream & ) 
    {
          xstream << "Hello!"; 
          return (xstream&)ostream::endl(xstream);
    }
    // ........
    // Insertions for other types
};