/*
 * Copyright (c) 2017 Peter D. Barnes, Jr.
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Authors:
 *   Tom Henderson <tomh@tomh.org>
 *   Mitch Watrous <watrous@u.washington.edu>
 *   Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
 *   Peter D. Barnes, Jr. <pdbarnes\llnl.gov>
 */

/**
 * @file
 * @ingroup core
 * This file provides some doxygen documentation for the core module.
 */

/**
 * @defgroup core Core
 * @brief The "core" module contains:
 *    - a time management class to hold a time and convert between various
 *      time units: ns3::Time
 *    - a scheduler base class used to implement new simulation event
 *      schedulers:
 *      ns3::Scheduler and ns3::SchedulerFactory
 *    - a simulator class used to create, schedule and cancel events:
 *      ns3::Simulator
 *    - a Functor class: ns3::Callback
 *    - an os-independent interface to get access to the elapsed wall clock
 *      time: ns3::SystemWallClockMs
 *    - a class to register regression tests with the test manager: ns3::Test
 *      and ns3::TestManager
 *    - debugging facilities: \ref debugging
 *    - \ref randomvariable
 *    - a base class for objects which need to support per-instance
 *      "attributes" and trace sources: ns3::ObjectBase
 *    - a base class for objects which need to support reference counting
 *      and dynamic object aggregation: ns3::Object
 *    - a smart-pointer class ns3::Ptr designed to work together with
 *      ns3::Object
 *    - a configuration class used to set and control all attributes and
 *      trace sources in a simulation: ns3::Config.
 *
 * @todo Move all Private and Impl classes to namespace ns3::impl?
 */

/**
 * @ingroup core
 * @defgroup debugging Debugging tools
 *
 * Assertions, breakpoints, logging, and abnormal program termination
 */

/**
 * @ingroup core
 * @defgroup core-examples Core module examples
 *  Programs which illustrate use of core module functionality.
 */

/**
 * @ingroup core
 * @defgroup core-helpers Core module helper classes
 * Helper classes for the Core module
 */

/**
 * @ingroup tests
 * @ingroup core
 * @defgroup core-tests Core module tests
 * TestSuites for the Core module
 */

/**
 * @ingroup core
 * @defgroup system System Services
 *
 * System-independent interfaces to operating system services:
 * environment variables, files system, threading, wall clock time.
 *
 * Services provided:
 *
 *   - Environment variables
 *   - File and directory paths.
 *   - Thread primitives:  threads, conditional waits, mutex, critical sections.
 *   - Asynchronous input from a file descriptor.
 *   - Wall clock time.
 */