Function<Object, Boolean> alwaysTrue = Functions.forPredicate(Predicates.alwaysTrue());
    Function<Object, Boolean> alwaysFalse = Functions.forPredicate(Predicates.alwaysFalse());

    assertTrue(alwaysTrue.apply(0));
    assertFalse(alwaysFalse.apply(0));

    new EqualsTester()
        .addEqualityGroup(alwaysTrue, Functions.forPredicate(Predicates.alwaysTrue()))
        .addEqualityGroup(alwaysFalse)

    Function<Object, Boolean> alwaysTrue = Functions.forPredicate(Predicates.alwaysTrue());
    Function<Object, Boolean> alwaysFalse = Functions.forPredicate(Predicates.alwaysFalse());

    assertTrue(alwaysTrue.apply(0));
    assertFalse(alwaysFalse.apply(0));

    new EqualsTester()
        .addEqualityGroup(alwaysTrue, Functions.forPredicate(Predicates.alwaysTrue()))
        .addEqualityGroup(alwaysFalse)

   * (Function<T, Boolean> & Serializable) predicate::test}.
   */
  public static <T extends @Nullable Object> Function<T, Boolean> forPredicate(
      Predicate<T> predicate) {
    return new PredicateFunction<>(predicate);
  }

  /**
   * @see Functions#forPredicate
   */
  private static final class PredicateFunction<T extends @Nullable Object>
      implements Function<T, Boolean>, Serializable {

      return components.hashCode() + 0x053c91cf;
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      if (obj instanceof OrPredicate) {
        OrPredicate<?> that = (OrPredicate<?>) obj;
        return components.equals(that.components);
      }
      return false;
    }

    @Override
    public String toString() {