Re: making friends with static members of template arguments

Hi,

I'm trying to make friends with static member functions
of template arguments:

<snip>
#include <iostream>
class some_policy {
public:
   template<class FooT>
   static void bar(const FooT *f) {
     std::cerr << f->a;
   }
};

template<class PolicyT>
class foo {
public:
   foo() : a(33) {
   }
   void bar() {
     PolicyT::bar(this);
   }
protected:
   int a;

   friend
   void PolicyT::bar< foo >(const foo *);
};

int main() {
   foo<some_policy> f;
   f.bar();
}
</snip>

So the idea is to specialize some behavior of the foo class in
class PolicyT which itself contains template static member
functions depending on the concrete foo class. I do not want
to make the whole PolicyT a template class since other static
member functions should only depend on some other internal
types of foo (kind of a replacement of partial template
specialization of foo members).

Everything works fine whenever I make 'int a' public and leave
out the 'friend..' part, but making the PolicyT::bar< foo>(...) a
friend fails

g++ 4.1.2 tells me

<snip>
test.cc:26: error: type ?PolicyT? is not derived from type ?foo<PolicyT>?
test.cc:26: error: expected ?;? before ?<? token
</snip>

Hmm... that's not very enlightening. Am I on the totally wrong trip
here or just in search for the proper syntax ?