protected FormValidator::performRequiredValidation(&$elements, FormStateInterface

public FormBuilder::__construct(FormValidatorInterface $form_validator, FormSubmitterInterface

public FormState::getSubmitHandlers() Gets

protected SubformState::__construct(array &$subform, array &$parent_form

public static OptGroup::flattenOptions(array $array) Allows

public BrokenPostRequestException::

public static FormState::hasAnyErrors() Determines

public FormCache::__construct($root, KeyValueExpirableFactoryInterface $key_val

public FormState::setFormState(array $form_state_additions)

Stores information about the state of a subform. In the context of Drupal's Form API, a subform is a form definition array that will be nested