MooTools (My Object-Oriented Tools)^[4] is a lightweight, object-oriented JavaScript framework. It is released under the free, open-source MIT License.^[5]

History

Valerio Proietti first authored the framework and released it in September 2006^[6] taking as his inspiration Prototype and Dean Edward's base2. MooTools originated from Moo.fx, a popular JavaScript effects library released in October 2005 by Valerio Proietti as an add-on to the Prototype Javascript Framework.^[7] which is still maintained and used. It can be used as a lighter alternative to script.aculo.us or other, bigger libraries. It provides simple, basic effects, and guarantees a small library size.

Whereas Prototype extended—prototyped—many of JavaScript's native String, Array, and Function objects with additional methods, Proietti desired a framework that (at the time)^[8] further extended the native Element object as well^[6] to offer greater control of the Document Object Model (DOM).^[9]

Components

MooTools includes a number of components, but not all need to be loaded for each application. Some of the component categories are:

• Core: A collection of utility functions that all the other components require.^[10]
• More: An official collection of add-ons that extend the Core and provide enhanced functionality.^[11]
• Class: The base library for Class object instantiation.^[12]
• Natives: A collection of JavaScript Native Object enhancements. The Natives add functionality, compatibility, and new methods that simplify coding.
• Element: Contains a large number of enhancements and compatibility standardization to the HTML Element object.^[13]
• Fx: An advanced effects-API to animate page elements.^[14]
• Request: Includes XHR interface, Cookie, JSON, and HTML retrieval-specific tools for developers to exploit.^[15]
• Window: Provides a cross-browser interface to client-specific information, such as the dimensions of the window.^[16]

Browser compatibility

MooTools is compatible and tested with:^[17]

• Safari 3+
• Internet Explorer 6+
• Mozilla Firefox 2+
• Opera 9+
• Chrome 4+

Benefits

MooTools provides the user with a number of advantages over native JavaScript. These include:

• An extensible and modular framework allowing developers to choose their own customized combination of components.^[18]
• MooTools follows object-oriented practices and the DRY principle.^[19]
• An advanced effects component, with optimized transitions such as easing equations used by many Flash developers.^[20]
• Enhancements to the DOM, enabling developers to easily add, modify, select, and delete DOM elements. Storing and retrieving information with Element storage is also supported.^[21]

The framework includes built-in functions for manipulation of CSS, DOM elements, native JavaScript objects, Ajax requests, DOM effects, and more. MooTools also provides a detailed, coherent application programming interface (API)^[22] as well as a custom downloads module allowing developers to download only the modules and dependencies they need for a particular app.^[23][24]

Emphasis on modularity and reusability

Every JavaScript framework has its philosophy, and MooTools is interested in taking full advantage of the flexibility and power of JavaScript in a way that emphasizes greater modularity and code reuse. MooTools accomplishes these goals in a way that is intuitive to a developer coming from a class-based inheritance language like Java with the MooTools Class object.

Class is an object of key/value pairs that can contain either properties or methods (functions). Class is effortlessly mixed and extended with other Class instantiations allowing for the greatest focus of MooTools: Code reuse achieved through maximizing the power of JavaScript's prototypical inheritance, but in a Class object syntax more familiar to classical inheritance models.^[25]

Object-oriented programming

MooTools contains a robust Class creation and inheritance system that resembles most classically based Object-oriented programming languages. For example, the following is MooTools' equivalent of the examples in Wikipedia's polymorphism page:

var Animal = new Class({

    initialize: function(name) {
        this.name = name;
    }

});

var Cat = new Class({
    Extends: Animal,

    talk: function() {
        return 'Meow!';
    }

});

var Dog = new Class({

    Extends: Animal,

    talk: function() {
        return 'Arf! Arf!';
    }

});

var animals = {
    a: new Cat('Missy'),
    b: new Cat('Mr. Bojangles'),
    c: new Dog('Lassie')
};

Object.each(animals, function(animal) {
    alert(animal.name + ': ' + animal.talk());
});
 
// alerts the following:
//
// Missy: Meow!
// Mr. Bojangles: Meow!
// Lassie: Arf! Arf!