!7

sclass X {
  S value;
  
  *() {}
  *(S *value) {}
}

p {
  Hasher<X> hasher = new Hasher<X>() {
    public int hashCode(X o) { ret _hashCode(o.value); }
    public bool equals(X a, X b) { ret a == null ? b == null : b != null && eq(a.value, b.value); }
  };
  
  CustomCompactHashSet<X> set = new(hasher);
  X x1 = X("hello");
  set.add(x1);
  assertTrue(set.contains(new X("hello")));
  assertFalse(set.contains(new X("world")));
  
  assertSame(x1, set.find(new X("hello")));
  assertNull(set.find(new X("world")));
  
  set.remove(x1);
  assertNull(set.find(new X("hello")));
  
  print("OK");
}