Re: Using directive/declaration and the global namespace

Indeed, according to Stroustrup `using N2::A' declaration should take
precedence ver all other names:

"When looking into a namespace, names explicitly declared there
(including names declared by using-declarations) take priority over
names made accessible in another scope by a using-directive (see also
?C.10.1)."

Also, both Stroustrup and C++ Standard emphasize that global space is
"just another namespace" without any special privileges. After playing a
little bit with the code I noticed that by specifying global namespace
for `A' I could solve ambiguity:

using namespace N1; // directive
using namespace N2; // directive
using N2::A; // declaration

void f()
{
  ::A a; // <- global scope
  a.F();
}

So, when qualified name is used, then no ambiguity exists. Currently I
don't have reasonable answer for this. I'll try to investigate it more
tomorrow.