#define FUNC_GEN9(x,y,z) anything
+#if defined(__cplusplus) && __cplusplus > 201703L
+
+# include <boost/preprocessor/variadic/has_opt.hpp>
+
+BEGIN BOOST_PP_IS_EMPTY(FUNC_GEN9) == BOOST_PP_VARIADIC_HAS_OPT() END
+
+#else
+
BEGIN BOOST_PP_IS_EMPTY(FUNC_GEN9) == 0 END
+#endif
+
#else
BEGIN 1 == 0 END