checkbox.js

(function () {
    'use strict';
    var checkbox = (function checkBoxBuilder() {
        var prototype = {
            values: function () {
                var keys = Object.keys(this);
                var type = this;
                return keys.filter(function (key) {
                    return type[key];
                });
            }
        };

        return function checkbox(obj) {
            obj = obj || {};
            var objDescriptor = {};
            Object.getOwnPropertyNames(obj).forEach(function (key) {
                try {
                    objDescriptor[key] = Object.getOwnPropertyDescriptor(obj, key);
                } catch (e) {
                    objDescriptor[key] = {
                        value: obj[key],
                        enumerable: true,
                        writable: true,
                        configurable: true
                    };
                }

            });
            return Object.create(prototype, objDescriptor);
        };
    }());

    var improvements = checkbox({a: true, b: false, c: true, d: false});
    console.log(improvements);
    console.log(improvements.values());
}());