Re: How can I declare and define a friend template function in a template class?

First, thank you for your informative tips, I rewrite my code snippet,
here it is:

#include <iostream>
using namespace std;

template<typename T>
class Test;

template<typename T>
Test<T> index(T start, T end, T step);

template<typename T>
class Test {
public:
   friend Test<T> index(T start, T end, T step);
};

template<typename T>
Test<T> index(T start, T end, T step) {
       cout << "This is index is working\n";
       return Test<T>();
}

int main() {

   int start;
   int end;
   int step;

   index(start, end, step);
}

It's the same as you think it is supposed to be, no problem with
compling and linking, but at runtime, a error is raised.