public class UnnamedPatterns {
record R(int a, int b) {}
void test(Object obj) {
if (obj instanceof _) {}
if (obj instanceof R(_, _)) {}
if (obj instanceof R(int a, _)) {
System.out.println(a);
}
if (obj instanceof R(_, int b)) {
System.out.println(b);
}
if (obj instanceof R(_, _, _)) {
}
}
}