Language Subtlety or Compiler bug?

From: Ned Harding (nharding_at_extendthereach.com)
Date: 08/31/04 

Date: 31 Aug 2004 10:25:03 -0700

In VC7.1 the following code outputs:
00000000
Success!

It would seem that the Y::operator<< is hiding the global operator<<
when it is outputting an object from another namespace but not when it
is outputting an object in the global namespace.

I can't help but think one of these 2 behaviors is a bug in VC7.1, but
which one?

Thanks,

Ned.

=========================================
#include <iostream>

namespace X
{
        class Abc1
        {
        };

}
std::ostream& operator<< (std::ostream& strm, const X::Abc1 *node)
{
        return strm << "Success!";
}

X::Abc1 * GetDoc() { return NULL; }

class Abc2
{
};

Abc2 * GetDoc2() { return NULL; }

std::ostream& operator<< (std::ostream& strm, const Abc2 *node)
{
        return strm << "Success!";
}

namespace Y
{
        std::ostream & operator<<(std::ostream& a, const char& b)
        {
                return a << "This should not run";
        }

        void DoTest()
        {
                std::cout << GetDoc() << "\n";
                std::cout << GetDoc2() << "\n";
        }
}

int main(int argc, char* argv[])
{
        Y::DoTest();
        return 0;
}

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