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+<?php
+
+/**
+ * @file
+ * Documentation landing page and topics, plus core library hooks.
+ */
+
+/**
+ * @mainpage
+ *
+ * Welcome to the Drupal developer documentation! This documentation is
+ * generated from specially-formatted comments embedded in the Drupal source
+ * code. Here are some topics to get you started.
+ *
+ * @section essentials Essential background concepts
+ *
+ * - @link architecture Drupal's architecture @endlink
+ * - @link extending Extending Drupal @endlink
+ * - @link oo_conventions Object-oriented conventions used in Drupal @endlink
+ * - @link best_practices Best practices @endlink
+ *
+ * @section interfacing Interfacing with the outside world
+ *
+ * - @link menu Routing, page controllers, and menu entries @endlink
+ * - @link form_api Forms @endlink
+ * - @link block_api Blocks @endlink
+ * - @link ajax Ajax @endlink
+ * - @link third_party Integrating third-party applications @endlink
+ *
+ * @section store_retrieve Storing and retrieving data
+ *
+ * - @link config_state Configuration and State system @endlink
+ * - @link entity_api Entities @endlink
+ * - @link field Fields @endlink
+ * - @link node_overview Node system @endlink
+ * - @link views_overview Views @endlink
+ * - @link database Database abstraction layer (Entity field queries, PDO)
+ *
+ * @section utility Utility APIs
+ *
+ * - @link i18n Internationalization @endlink
+ * - @link cache Caching @endlink
+ * - @link user_api User accounts, permissions, and roles @endlink
+ * - @link theme_render Theme system and render API @endlink
+ *
+ * @section advanced Advanced topics
+ *
+ * - @link container Services and the Dependency Injection Container @endlink
+ * - @link typed_data Typed Data @endlink
+ * - @link migration Migration @endlink
+ * - @link testing Automated tests @endlink
+ *
+ * @section more_info Further information
+ *
+ * - @link https://api.drupal.org/api/drupal/groups/8 All topics @endlink
+ * - @link https://drupal.org/project/examples Examples project (sample modules) @endlink
+ * - @link https://drupal.org/list-changes API change notices @endlink
+ * - @link https://drupal.org/developing/api/8 Drupal 8 API longer references @endlink
+ */
+
+/**
+ * @defgroup block_api Block API
+ * @{
+ * Information about the classes and interfaces that make up the Block API.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and classes and
+ * interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/2168137
+ * @}
+ */
+
+/**
+ * @defgroup third_party REST and Application Integration
+ * @{
+ * Integrating third-party applications using REST and related operations.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ * @}
+ */
+
+
+/**
+ * @defgroup config_state Configuration and State Systems
+ * @{
+ * Information about the Configuration system and the State system.
+ *
+ * @todo write this
+ *
+ * This topic needs to describe simple configuration, configuration entities,
+ * and the state system, at least at an overview level, and link to more
+ * information (either drupal.org or more detailed topics in the API docs).
+ *
+ * See https://drupal.org/node/1667894
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ * @}
+ */
+
+/**
+ * @defgroup entity_api Entity API
+ * @{
+ * Describes how to define and manipulate content and configuration entities.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic. Should describe
+ * bundles, entity types, configuration vs. content entities, etc. at an
+ * overview level. And link to more detailed documentation.
+ *
+ * See https://drupal.org/developing/api/entity
+ * @}
+ */
+
+/**
+ * @defgroup node_overview Nodes Overview
+ * @{
+ * Overview of how to interact with the Node system
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic. This topic should
+ * describe node access, the node classes/interfaces, and the node hooks that a
+ * developer would need to know about, at a high level, and link to more
+ * detailed information.
+ *
+ * @see node_access
+ * @see node_api_hooks
+ * @}
+ */
+
+/**
+ * @defgroup views_overview Views overview
+ * @{
+ * Overview of the Views module API
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic. Should link to all
+ * or most of the existing Views topics, and maybe this should be moved into
+ * a different file? This topic should be an overview so that developers know
+ * which of the many Views classes and topics are important if they want to
+ * accomplish tasks that they may have.
+ * @}
+ */
+
+
+/**
+ * @defgroup i18n Internationalization
+ * @{
+ * Internationalization and translation
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/2133321
+ * @}
+ */
+
+/**
+ * @defgroup cache Cache API
+ * @{
+ * Information about the Drupal Cache API
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * @see https://drupal.org/node/1884796
+ * @}
+ */
+
+/**
+ * @defgroup user_api User Accounts System
+ * @{
+ * API for user accounts, access checking, roles, and permissions.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ * @}
+ */
+
+/**
+ * @defgroup theme_render Theme system and Render API
+ * @{
+ * Overview of the theme system and render API
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ * @}
+ */
+
+/**
+ * @defgroup container Services and Dependency Injection Container
+ * @{
+ * Overview of the Dependency Injection Container and Services.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/2133171
+ * @}
+ */
+
+/**
+ * @defgroup typed_data Typed Data API
+ * @{
+ * API for defining what type of data is used in fields, configuration, etc.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/1794140
+ * @}
+ */
+
+/**
+ * @defgroup migration Migration API
+ * @{
+ * Overview of the Migration API, which migrates data into Drupal.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/2127611
+ * @}
+ */
+
+/**
+ * @defgroup testing Automated tests
+ * @{
+ * Overview of PHPUnit tests and Simpletest tests.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/simpletest
+ * @}
+ */
+
+/**
+ * @defgroup architecture Architecture overview
+ * @{
+ * Overview of Drupal's architecture for developers.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * Should include: modules, info.yml files, location of files, etc.
+ * @}
+ */
+
+/**
+ * @defgroup extending Extending Drupal
+ * @{
+ * Overview of hooks, plugins, annotations, event listeners, and services.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic. This should be
+ * high-level and link to more detailed topics.
+ * @}
+ */
+
+/**
+ * @defgroup oo_conventions Objected-oriented programming conventions
+ * @{
+ * PSR-4, namespaces, class naming, and other conventions.
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/node/608152 and links therein for references. This
+ * should be an overview and link to details. It needs to cover: PSR-*,
+ * namespaces, link to reference on OO, class naming conventions (base classes,
+ * etc.), and other things developers should know related to object-oriented
+ * coding.
+ * @}
+ */
+
+/**
+ * @defgroup best_practices Best practices for developers
+ * @{
+ * Overview of best practices for developers
+ *
+ * @todo write this
+ *
+ * Additional documentation paragraphs need to be written, and functions,
+ * classes, and interfaces need to be added to this topic.
+ *
+ * See https://drupal.org/developing/best-practices -- this should touch upon
+ * (and link to more information on): internationalization, security, automated
+ * tests, documentation.
+ * @}
+ */