Which JavaScript Library Has the Most Comprehensive Class Inheritance Support? [closed]

I found out there is a Javascript Framework modeled after Ruby:

Js.Class

Another good one is:

Joose-js (modeled after moose (perl) )

I prefer Josse, because it seems to be more actively developed, and the syntax looks neat too!

Any thoughts??? (Maybe this should be another question??)

I think Microsoft Ajax implements it just perfectly (with namespaces, inheritance & interfaces etc.)

Sample:

Type.registerNamespace("Demo");

Demo.Person = function(firstName, lastName, emailAddress) {
    this._firstName = firstName;
    this._lastName = lastName;
    this._emailAddress = emailAddress;
}

Demo.Person.prototype = {

    getFirstName: function() {
        return this._firstName;
    },

    getLastName: function() {
        return this._lastName;
    },

    getName: function() {
        return this._firstName + ' ' + this._lastName;
    },

    dispose: function() {
        alert('bye ' + this.getName());
    }
}
Demo.Person.registerClass('Demo.Person', null, Sys.IDisposable);

// Notify ScriptManager that this is the end of the script.
if (typeof(Sys) !== 'undefined') Sys.Application.notifyScriptLoaded();

You should try Classy:

http://classy.pocoo.org/

It is simple and really small but has everything I need when constructing my classes.

Check out Prototype. Here's a sample:

// properties are directly passed to `create` method
var Person = Class.create({
  initialize: function(name) {
    this.name = name;
  },
  say: function(message) {
    return this.name + ': ' + message;
  }
});

// when subclassing, specify the class you want to inherit from
var Pirate = Class.create(Person, {
  // redefine the speak method
  say: function($super, message) {
    return $super(message) + ', yarr!';
  }
});

var john = new Pirate('Long John');
john.say('ahoy matey');
// -> "Long John: ahoy matey, yarr!"

Base2 has simple inheritance mechanism , See John Resig's post on this (comments in the post are also interesting).

Something to also keep in mind is that trying to do simulate classic OO in Javascript has been getting lot of flak lately (although it was explored very enthusiastically in the initial days of great JS library revolution).

You might also be interested in qooxdoo, a framework for creating rich internet applications (RIAs). It includes a comprehensive OO layer, which aims at being powerful, elegant and fast:

See the following section in the manual, which has all the details: http://qooxdoo.org/documentation/0.8#object_orientation

I find mootools to be everything I need for inheritence. It uses the basic motif of Extends and Implements of many other OO languages.

One of the developers goes over it in detail in his comparison to jquery:

http://jqueryvsmootools.com

You don't need the whole library either. You can just download their Class model and ignore the rest (animation, dom manipulation, etc).

Just pick whichever one "tastes" best to you. In the end, they all use prototypal inheritance behind the scenes, so they all have roughly the same level of functionality.

If you want a high-powered traditional class system, use GWT and program in pure Java.

Personally I prefer Ext's component system, but that's because Ext components actually have a full lifecycle (initialization, rendering, state persistence and destruction), which in turn allows component plugins that don't break with minor updates to the library.

Well, first you should ask if you want a library that tries to emulate classical inheritance or one that goes more for JS's native prototypal inheritance.

DUI (the Digg User Interface library) is a jQuery addon that takes Prototype's old model and extends it in a much more intuitive way, allowing for nested static and dynamic classes, namespaces, support for the dontEnum bit and more. Documentation is available on Digg's GitHub. I think you'll find it pretty robust.

Disclosure: I work for Digg and wrote DUI ;)