forward class friend declaration
<p>Hi i have a problem, I try to do the follow, class A depends on class B and vice versa like this</p>

<pre><code>class A;

 class B{
   A foo;
   friend B A::doSomething();

 };

class A {
   B bar;
   B doSomething;
};
</code></pre>

<p>The friend declartion does not work because A is an incomplete declartion. Is there any way to avoid this? (Swapp classes declaration order is not a solution I did not want to construct a more complicated example where swapping does not work anymore)</p>
