The URL generator. Type:

public ConfirmFormBase::buildForm(array $form, FormStateInterface $

public FormCache::deleteCache($form_build_id) Deletes

A policy rule determining the cacheability of a request. Type:

protected FormBase::getRequest() Gets the

public FormSubmitterInterface::executeSubmitHandlers(&$form

public FormStateDecoratorBase::setError(array &$element

A wrapper containing a response which is to be enforced upon delivery. The FormBuilder throws an EnforcedResponseException whenever a form desires

public FormStateDecoratorBase::setAlwaysProcess($always_process

public FormStateDecoratorBase::isProcessingInput()