edlp_d8/core/lib/Drupal/Core/Render/Element/PageTitle.php

<?php

namespace Drupal\Core\Render\Element;

/**
 * Provides a render element for the title of an HTML page.
 *
 * This represents the title of the HTML page's body.
 *
 * @RenderElement("page_title")
 */
class PageTitle extends RenderElement {

  /**
   * {@inheritdoc}
   */
  public function getInfo() {
    return [
      '#theme' => 'page_title',
      // The page title: either a string for plain titles or a render array for
      // formatted titles.
      '#title' => NULL,
    ];
  }

}