so_class.js

/**
 * @package so
 * @object  so.class
 * @depends so
 * @author  Kerem Güneş
 * @license The MIT License <https://opensource.org/licenses/MIT>
 */
;(function ($) { 'use strict';

    var PROTOTYPE = 'prototype', $extend = $.extend;

    /**
     * Class.
     * @param  {Function} subClass
     * @return {Object}
     */
    var $class = function (subClass) {
        return {
            /**
             * Extends.
             * @param  {Function} supClass
             * @return {Function}
             */
            extends: function (supClass) {
                // @note: super() always must be called in subClass constructor
                var prototype = $extend(
                    {}, supClass[PROTOTYPE], subClass[PROTOTYPE],
                    {constructor: subClass, super: supClass}
                );

                subClass[PROTOTYPE] = Object.create(prototype);

                return subClass;
            }
        }
    };

    /**
     * Extend.
     * @param  {Function} target
     * @param  {Object}   prototype
     * @return {Function}
     */
    $class.extend = function (target, prototype) {
        return $extend(target[PROTOTYPE], prototype);
    },

    // export
    $.class = $class;

})(window.so);