class xyz {
public:
    static int abc();
};

#include xyz.h

namespace xyz {

class qwe{
public:
    void bnm() {
        int value = xyz::abc();

    }
};

}

xyz       ab;   // The defn is ambiguous.
class xyz ab;   // The ambiguity is resolved.

class xyz dummy;
int value = dummy.abc();

namespace othername {
   #include "xyz.h"
}

othername::xyz::abc();