reference to function and pointer to function

 Now, you are amazed and you may ask: what is reference to function? A reference to function is a function alias which repersent the function. Follow is a demo of reference to function.

template <class T1, class T2, class T3>
T1 sum(T2 p1, T3 p2) ...{
    cout << "three parameters" << endl;
    return p1 + p2;
}

int main()
...{
    int (&pr)(char,int) = sum<int>; // fp is reference to function    
    cout << typeid(pr).name() << endl; // print: "int __cdecl(char,int)" in VS2008
}

Ok!It is the time to see pointer to function and code is the best word in our world.

template <class T1, class T2, class T3>
T1 sum(T2 p1, T3 p2) ...{
    cout << "three parameters" << endl;
    return p1 + p2;
}

int main()
...{
    int (*fp)(char,int) = &sum<int>; // fp is reference to function    
    cout << typeid(fp).name() << endl; // print: "int (__cdecl*)(char,int)" in VS2008
}