AMD-compatible CommonJS Module/1.1 that can also be loaded in a script tag

dual.js

(function (define) {

    define(function (exports) {
        function Color(){}
        return Color;
    });

}(
    // provide define if it's not available
    this.define || (function (global, moduleId) {
        return function (defFunc) {
            global[moduleId] = defFunc({});
        }
    })(this, 'Color')
));