svoid test_PersistentManagedObjects_v1() {
  new ManagedIntObjects_v1 mem;
  PersistentManagedObjects_v1<ManagedString> pm = new(mem, (_mem, addr) -> ManagedString.load(_mem, addr));
  ManagedString s = pm.getUserData();
  assertNullVerbose("userData", s);
  pm.setUserData(ManagedString.create(mem, "Hello world"));
  s = pm.getUserData();
  assertEqualsVerbose("Hello world", str(s));
  print("Mem size: " + mem.size());
  
  mem = new ManagedIntObjects_v1(mem.mem);
  pm = new PersistentManagedObjects_v1<ManagedString>(mem, pm.makeUserObject);
  assertEqualsVerbose("Hello world", str(s));
}