Re: Declaring a template class with two template params a friend in a non-template class

I have an abstract class:

class Attribute { /* ...*/ };

Now I have another class:

template <typename T, typename U>
class Mgr
{
    static U *create(const std::string k, std::string v)
    {
        static T *p = 0;
        if (!p)
        {
            p = new T();
        }
        T &r = *p;
        U *a = const_cast<U*>(r.get(k));
        return a;
    }

};

Both of these classes are declared/defined in different header files.

The problem is that the constructors of Attribute class are private so
I have to declare the Mgr class a friend of Attribute. That's what I
have a problem doing - I am having a difficult time with the template
syntax when it comes to declaring a template class (with two template
parameters) a friend in a non-template class - I am getting lots of
compilation errors on the friend template declaration. Can any kind
sole tell me how I am supposed to do it? Declare a template class with
two template parameters a friend in a non-template class???