init.php

<?php
/**
 * Custom Tables Loader
 *
 * Handles checking for and smartly loading the newest version of this library.
 *
 * @category  WordPressLibrary
 * @package   Custom_Tables\Loader
 * @author    GamiPress <contact@gamipress.com>, Ruben Garcia <rubengcdev@gamil.com>
 * @copyright GamiPress <contact@gamipress.com>, Ruben Garcia <rubengcdev@gamil.com>
 * @credits   Justin Sternberg (https://jtsternberg.com), Jhon James Jacob (https://jjj.blog)
 * @license   GPL-2.0+
 * @version   1.0.7
 * @link      https://gamipress.com
 */

/*
 * Copyright (c) GamiPress (contact@gamipress.com), Ruben Garcia (rubengcdev@gmail.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 or, at
 * your discretion, any later version, as published by the Free
 * Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

/**
 * Loader versioning: http://jtsternberg.github.io/wp-lib-loader/
 */
if ( ! class_exists( 'CT_Loader_107', false ) ) {

    class CT_Loader_107 {

        /**
         * CT_Loader version number
         * @var   string
         * @since 1.0.0
         */
        const VERSION = '1.0.7';

        /**
         * Setup constants
         *
         * @since       1.0.0
         */
        private function constants() {

            // Version
            define( 'CT_VER', self::VERSION );

            // File
            define( 'CT_FILE', __FILE__ );

            // Path
            define( 'CT_DIR', plugin_dir_path( __FILE__ ) );

            // URL
            define( 'CT_URL', plugin_dir_url( __FILE__ ) );

            // Debug
            define( 'CT_DEBUG', false );

        }

        /**
         * Starts the version checking process.
         * Creates CT_LOADED definition for early detection by other scripts.
         *
         * Hooks CT_Loader inclusion to the ct_loader_load hook
         * on a high priority which decrements (increasing the priority) with
         * each version release.
         *
         * @since 1.0.0
         */
        public function __construct() {

            if ( ! defined( 'CT_LOADER_PRIORITY' ) ) {
                // Calculate priority converting version into a number (eg: 1.0.0 to 100)
                define( 'CT_LOADER_PRIORITY', 99999 - absint( str_replace( '.', '', self::VERSION ) ) );
            }

            if ( ! defined( 'CT_LOADED' ) ) {
                // A constant you can use to check if Custom Tables (CT) is loaded for your plugins/themes with CT dependency.
                // Can also be used to determine the priority of the hook in use for the currently loaded version.
                define( 'CT_LOADED', CT_LOADER_PRIORITY );
            }

            // Use the hook system to ensure only the newest version is loaded.
            add_action( 'ct_loader_load', array( $this, 'include_lib' ), CT_LOADER_PRIORITY );

            // Try to fire our hook as soon as possible,including right now (required for activation hooks).
            self::fire_hook();

            // Hook in to the first hook we have available and fire our `ct_loader_load' hook.
            add_action( 'muplugins_loaded', array( __CLASS__, 'fire_hook' ), 9 );
            add_action( 'plugins_loaded', array( __CLASS__, 'fire_hook' ), 9 );
            add_action( 'after_setup_theme', array( __CLASS__, 'fire_hook' ), 9 );
        }

        /**
         * Fires the ct_loader_load action hook.
         *
         * @since 1.0.0
         */
        public static function fire_hook() {
            if ( ! did_action( 'ct_loader_load' ) ) {
                // Then fire our hook.
                do_action( 'ct_loader_load' );
            }
        }

        /**
         * A final check if CT_Loader exists before kicking off
         * our CT_Loader loading.
         *
         * @since  1.0.0
         */
        public function include_lib() {
            if ( class_exists( 'CT', false ) ) {
                return;
            }

            $this->constants();

            // Include and initiate Custom Tables (CT) class.
            require_once CT_DIR . 'includes/class-ct.php';
        }

    }

    // Kick it off.
    new CT_Loader_107;
}