!752

p {
  S a = rep('a', 100);
  S s = structure(ll(a, a));
  print(s);
  assertTrue("length " + l(s), l(s) < 200);
  L<S> l = cast unstructure(s);
  assertEquals(ll(a, a), l);
  assertSame(l.get(0), l.get(1));
  print("OK!!");
}