class C_A {
public:
	struct S_A {	int x;	S_A() : x(1) {} };
};
class C_B : public C_A {
public:
	struct S_B : public S_A {	S_B() { x = 3; } };
};
C_B::S_B b;

CONSOLE_APP_MAIN
{
	UPP::Cout().Put( UPP::AsString(b.x) + "\r\n" );
//put "b." here, the "x" of S_A will be not shown
}