Ordering<Number> unusedF = numbers.compound(objects).compound(objects); // bad IDEA
    Ordering<Number> unusedG = objects.compound(numbers).compound(objects);
    Ordering<Number> unusedH = objects.compound(objects).compound(numbers);

    Ordering<Number> unusedI = numbers.compound(objects.compound(objects));
    Ordering<Number> unusedJ = objects.compound(numbers.compound(objects)); // bad IDEA

    Ordering<Number> unusedF = numbers.compound(objects).compound(objects); // bad IDEA
    Ordering<Number> unusedG = objects.compound(numbers).compound(objects);
    Ordering<Number> unusedH = objects.compound(objects).compound(numbers);

    Ordering<Number> unusedI = numbers.compound(objects.compound(objects));
    Ordering<Number> unusedJ = objects.compound(numbers.compound(objects)); // bad IDEA

   * status and second by priority, you might use {@code byStatus.compound(byPriority)}. For a
   * compound ordering with three or more components, simply chain multiple calls to this method.
   *
   * <p>An ordering produced by this method, or a chain of calls to this method, is equivalent to
   * one created using {@link Ordering#compound(Iterable)} on the same component comparators.
   *

   * status and second by priority, you might use {@code byStatus.compound(byPriority)}. For a
   * compound ordering with three or more components, simply chain multiple calls to this method.
   *
   * <p>An ordering produced by this method, or a chain of calls to this method, is equivalent to
   * one created using {@link Ordering#compound(Iterable)} on the same component comparators.
   *

  public Set<Feature<? super Collection>> getImpliedFeatures() {
    return implied;
  }

  public int getNumElements() {
    if (numElements == null) {
      throw new IllegalStateException(
          "A compound CollectionSize doesn't specify a number of elements.");
    }
    return numElements;
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited
  @TesterAnnotation
  public @interface Require {

///

**FastAPI** will do the automatic conversion from the request, so that the parameter `item` receives its specific content and the same for `user`.

It will perform the validation of the compound data, and will document it like that for the OpenAPI schema and automatic docs.

## Singular values in body

    // to fill dummy parameter values for them. Ties are broken by name then by the string form of
    // the parameter list.
    return BY_NUMBER_OF_PARAMETERS
        .compound(BY_METHOD_NAME)
        .compound(BY_PARAMETERS)
        .immutableSortedCopy(factories);
  }

  private List<Object> getDummyArguments(Invokable<?, ?> invokable)
      throws ParameterNotInstantiableException {