ImmutableSortedSet<Integer> set = ImmutableSortedSet.of(2, 4, 6, 8, 10);
    ImmutableSortedSet<Integer> empty = ImmutableSortedSet.of();

    assertEquals(set, Sets.subSet(set, Range.closed(0, 12)));
    assertEquals(ImmutableSortedSet.of(2, 4), Sets.subSet(set, Range.closed(0, 4)));
    assertEquals(ImmutableSortedSet.of(2, 4, 6), Sets.subSet(set, Range.closed(2, 6)));

    ImmutableSortedMap<Integer, Integer> map = ImmutableSortedMap.of(2, 0, 4, 0, 6, 0, 8, 0, 10, 0);
    ImmutableSortedMap<Integer, Integer> empty = ImmutableSortedMap.of();

    assertEquals(map, Maps.subMap(map, Range.closed(0, 12)));
    assertEquals(ImmutableSortedMap.of(2, 0, 4, 0), Maps.subMap(map, Range.closed(0, 4)));
    assertEquals(ImmutableSortedMap.of(2, 0, 4, 0, 6, 0), Maps.subMap(map, Range.closed(2, 6)));

    ImmutableSortedMap<Integer, Integer> map = ImmutableSortedMap.of(2, 0, 4, 0, 6, 0, 8, 0, 10, 0);
    ImmutableSortedMap<Integer, Integer> empty = ImmutableSortedMap.of();

    assertEquals(map, Maps.subMap(map, Range.closed(0, 12)));
    assertEquals(ImmutableSortedMap.of(2, 0, 4, 0), Maps.subMap(map, Range.closed(0, 4)));
    assertEquals(ImmutableSortedMap.of(2, 0, 4, 0, 6, 0), Maps.subMap(map, Range.closed(2, 6)));

    a = ImmutableList.of(4, 8, 15, 16, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertTrue(Iterators.elementsEqual(a.iterator(), b.iterator()));

    // An element differs.
    a = asList(4, 8, 15, 12, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertFalse(Iterators.elementsEqual(a.iterator(), b.iterator()));

    // null versus non-null.
    a = Arrays.<@Nullable Integer>asList(4, 8, 15, null, 23, 42);

  // Timed Get
  // There are a few design constraints to consider
  // * We want to be responsive to small timeouts, unpark() has non trivial latency overheads (I
  //   have observed 12 micros on 64-bit linux systems to wake up a parked thread). So if the
  //   timeout is small we shouldn't park(). This needs to be traded off with the cpu overhead of

    a = ImmutableList.of(4, 8, 15, 16, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertTrue(Iterators.elementsEqual(a.iterator(), b.iterator()));

    // An element differs.
    a = asList(4, 8, 15, 12, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertFalse(Iterators.elementsEqual(a.iterator(), b.iterator()));

    // null versus non-null.
    a = Arrays.<@Nullable Integer>asList(4, 8, 15, null, 23, 42);