assertNull(k);
                      return v3();
                    }));
    expectUnchanged();
    expectNullKeyMissingWhenNullKeysUnsupported(
        "Should not contain null key after unsupported computeIfAbsent(null, function)");
  }

 *       href="https://bugs.openjdk.java.net/browse/JDK-8202469">JDK-8202469</a>
 * </ul>
 *
 * <p>This annotation is a temporary hack. We will remove it after we're able to adopt the <a
 * href="https://jspecify.dev/">JSpecify</a> nullness annotations and <a
 * href="https://github.com/google/guava/issues/6126#issuecomment-1203145963">tools no longer need
 * it</a>.
 */

        sb.append(comp);
        delim = DELIMITER_STRING;
      }
      dummy ^= sb.toString().length();
    }
    return dummy;
  }

  /**
   * Always append the delimiter after the component, and in the very end shortens the buffer to get
   * rid of the extra trailing delimiter.
   */
  @Benchmark
  int alwaysAppendThenBackUp(int reps) {
    int dummy = 0;

 *       href="https://bugs.openjdk.java.net/browse/JDK-8202469">JDK-8202469</a>
 * </ul>
 *
 * <p>This annotation is a temporary hack. We will remove it after we're able to adopt the <a
 * href="https://jspecify.dev/">JSpecify</a> nullness annotations and <a
 * href="https://github.com/google/guava/issues/6126#issuecomment-1203145963">tools no longer need
 * it</a>.
 */

 *
 * @author Dimitris Andreou
 */
@Immutable
@ElementTypesAreNonnullByDefault
abstract class AbstractCompositeHashFunction extends AbstractHashFunction {

  @SuppressWarnings("Immutable") // array not modified after creation
  final HashFunction[] functions;

  AbstractCompositeHashFunction(HashFunction... functions) {
    for (HashFunction function : functions) {
      checkNotNull(function);
    }
    this.functions = functions;

// but without constructing the slice.
// It returns a single-use iterator.
func SplitSeq(s, sep []byte) iter.Seq[[]byte] {
	return splitSeq(s, sep, 0)
}

// SplitAfterSeq returns an iterator over substrings of s split after each instance of sep.
// The iterator yields the same strings that would be returned by SplitAfter(s, sep),
// but without constructing the slice.
// It returns a single-use iterator.

    }

    protected void registerSpecifiedProperty(String propertyName) { // basically called by modified property registration
        if (__specifiedProperties != null) { // normally false, true if e.g. setting after selected
            __specifiedProperties.addPropertyName(propertyName);
        }
    }

    // ===================================================================================

  public void testAdd_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> collection.add(null));
    expectUnchanged();
    expectNullMissingWhenNullUnsupported("Should not contain null after unsupported add(null)");
  }

  @CollectionFeature.Require({SUPPORTS_ADD, FAILS_FAST_ON_CONCURRENT_MODIFICATION})
  @CollectionSize.Require(absent = ZERO)
  public void testAddConcurrentWithIteration() {
    assertThrows(

  public void testAdd_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> collection.add(null));
    expectUnchanged();
    expectNullMissingWhenNullUnsupported("Should not contain null after unsupported add(null)");
  }

  @CollectionFeature.Require({SUPPORTS_ADD, FAILS_FAST_ON_CONCURRENT_MODIFICATION})
  @CollectionSize.Require(absent = ZERO)
  public void testAddConcurrentWithIteration() {
    assertThrows(

    assertThrows(NullPointerException.class, () -> getList().addAll(0, containsNull));
    expectUnchanged();
    expectNullMissingWhenNullUnsupported(
        "Should not contain null after unsupported addAll(n, containsNull)");
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testAddAllAtIndex_middle() {
    assertTrue(