assertEquals(expected, matcher.toString());
    assertEquals(expected, matcher.precomputed().toString());
    assertEquals(expected, matcher.negate().negate().toString());
    assertEquals(expected, matcher.negate().precomputed().negate().toString());
    assertEquals(expected, matcher.negate().precomputed().negate().precomputed().toString());
  }

    assertEquals(expected, matcher.toString());
    assertEquals(expected, matcher.precomputed().toString());
    assertEquals(expected, matcher.negate().negate().toString());
    assertEquals(expected, matcher.negate().precomputed().negate().toString());
    assertEquals(expected, matcher.negate().precomputed().negate().precomputed().toString());
  }

   * probability.
   */
  static BigInteger randomNonZeroBigInteger(int numBits) {
    BigInteger result = randomPositiveBigInteger(numBits);
    return RANDOM_SOURCE.nextBoolean() ? result : result.negate();
  }

  /**
   * Chooses a number in (-2^numBits, 2^numBits) at random, with density concentrated in numbers of
   * lower magnitude.
   */
  static BigInteger randomBigInteger(int numBits) {

    }
  }

  // Non-static factory implementation classes

  /** Implementation of {@link #negate()}. */
  private static class Negated extends CharMatcher {

    final CharMatcher original;

    Negated(CharMatcher original) {
      this.original = checkNotNull(original);
    }

    @Override
    public boolean matches(char c) {

   * probability.
   */
  static BigInteger randomNonZeroBigInteger(int numBits) {
    BigInteger result = randomPositiveBigInteger(numBits);
    return RANDOM_SOURCE.nextBoolean() ? result : result.negate();
  }

  /**
   * Chooses a number in (-2^numBits, 2^numBits) at random, with density concentrated in numbers of
   * lower magnitude.
   */
  static BigInteger randomBigInteger(int numBits) {

  }

  public void testCheckPositive_negativeBigInteger() {
    assertThrows(
        IllegalArgumentException.class,
        () -> MathPreconditions.checkPositive("BigInteger", BigInteger.ZERO.negate()));
  }

  public void testCheckNonNegative_zeroInt() {
    MathPreconditions.checkNonNegative("int", 0);
  }

  public void testCheckNonNegative_maxInt() {

        .roundUnnecessaryShouldThrow()
        .test();
  }

  public void testRoundToDouble_negativeWayTooBig() {
    BigDecimal bi = BigDecimal.valueOf(2).pow(2 * Double.MAX_EXPONENT).negate();
    new RoundToDoubleTester(bi)
        .setExpectation(-Double.MAX_VALUE, DOWN, CEILING, HALF_EVEN, HALF_UP, HALF_DOWN)
        .setExpectation(Double.NEGATIVE_INFINITY, UP, FLOOR)
        .roundUnnecessaryShouldThrow()

// including timezone is ignored.
func dateDiff(timePart string, ts1, ts2 time.Time) (*Value, error) {
	if ts2.Before(ts1) {
		v, err := dateDiff(timePart, ts2, ts1)
		if err == nil {
			v.negate()
		}
		return v, err
	}

	duration := ts2.Sub(ts1)
	y1, m1, d1 := ts1.Date()
	y2, m2, d2 := ts2.Date()

	switch timePart {
	case timePartYear:
		dy := int64(y2 - y1)

	l.mutex.Lock()
	defer l.mutex.Unlock()
	if _, reply = l.lockMap[args.Resources[0]]; !reply {
		l.lockMap[args.Resources[0]] = WriteLock // No locks held on the given name, so claim write lock
	}
	reply = !reply // Negate *reply to return true when lock is granted or false otherwise
	return reply, nil
}

func (l *lockServer) Unlock(args *LockArgs) (reply bool, err error) {
	if d := atomic.LoadInt64(&l.responseDelay); d != 0 {

      };

  private static final Function<BigInteger, BigInteger> NEGATE_BIGINT =
      new Function<BigInteger, BigInteger>() {
        @Override
        public BigInteger apply(BigInteger x) {
          return x.negate();
        }
      };

  /*
   * This list contains values that attempt to provoke overflow in integer operations. It contains
   * positive values on or near 2^N for N near multiples of 8 (near byte boundaries).