WordPress/wp-includes/widgets.php

<?php
/**
 * API for creating dynamic sidebar without hardcoding functionality into
 * themes. Includes both internal WordPress routines and theme use routines.
 *
 * This functionality was found in a plugin before WordPress 2.2 release which
 * included it in the core from that point on.
 *
 * @link https://codex.wordpress.org/Plugins/WordPress_Widgets WordPress Widgets
 * @link https://codex.wordpress.org/Plugins/WordPress_Widgets_Api Widgets API
 *
 * @package WordPress
 * @subpackage Widgets
 */

/* Global Variables */

/** @ignore */
global $wp_registered_sidebars, $wp_registered_widgets, $wp_registered_widget_controls, $wp_registered_widget_updates;

/**
 * Stores the sidebars, since many themes can have more than one.
 *
 * @global array $wp_registered_sidebars
 * @since 2.2.0
 */
$wp_registered_sidebars = array();

/**
 * Stores the registered widgets.
 *
 * @global array $wp_registered_widgets
 * @since 2.2.0
 */
$wp_registered_widgets = array();

/**
 * Stores the registered widget control (options).
 *
 * @global array $wp_registered_widget_controls
 * @since 2.2.0
 */
$wp_registered_widget_controls = array();
/**
 * @global array $wp_registered_widget_updates
 */
$wp_registered_widget_updates = array();

/**
 * Private
 *
 * @global array $_wp_sidebars_widgets
 */
$_wp_sidebars_widgets = array();

/**
 * Private
 *
 * @global array $_wp_deprecated_widgets_callbacks
 */
$GLOBALS['_wp_deprecated_widgets_callbacks'] = array(
	'wp_widget_pages',
	'wp_widget_pages_control',
	'wp_widget_calendar',
	'wp_widget_calendar_control',
	'wp_widget_archives',
	'wp_widget_archives_control',
	'wp_widget_links',
	'wp_widget_meta',
	'wp_widget_meta_control',
	'wp_widget_search',
	'wp_widget_recent_entries',
	'wp_widget_recent_entries_control',
	'wp_widget_tag_cloud',
	'wp_widget_tag_cloud_control',
	'wp_widget_categories',
	'wp_widget_categories_control',
	'wp_widget_text',
	'wp_widget_text_control',
	'wp_widget_rss',
	'wp_widget_rss_control',
	'wp_widget_recent_comments',
	'wp_widget_recent_comments_control'
);

require_once( ABSPATH . WPINC . '/class-wp-widget.php' );
require_once( ABSPATH . WPINC . '/class-wp-widget-factory.php' );
require_once( ABSPATH . WPINC . '/widget-functions.php' );