BADMACRO

demo.cpp

#define BADMACRO(t, s, f) \
{\
 ##t str[] = s; \
 f << str << endl; \
}

#define BADMACRO2(t, s, f) \
{ \
 BADMACRO(##t, ##s, ##f) \
}


int main()
{
	BADMACRO(WCHAR, L"String1", wcout);
	BADMACRO(CHAR, "String2", cout);
	BADMACRO2(WCHAR, L"String3", wcout);
	BADMACRO2(CHAR, "String4", cout);
}

// After preprocessing: 

int main()
{
	{WCHAR str[] = L"String1"; wcout << str << endl; };
	{CHAR str[] = "String2"; cout << str << endl; };
	{ {WCHAR str[] = L"String3"; wcout << str << endl; } };
	{ {CHAR str[] = "String4"; cout << str << endl; } };
}