Chic

Chic is an extremely simple class-like interface to JavaScript prototypal inheritance.

Current Stable Version: 1.0.1
Automated Build Status:
Node Support: 0.6, 0.8
Browser Support: Android Browser 2.2–4.2, Firefox 3.6, Firefox 4–16, Google Chrome 14–23, Internet Explorer 6–10, Mobile Safari iOS 4–6, Opera 12.10, Safari 5–6

Getting Started

You can use Chic on the server side with Node.js and npm:

$ npm install chic

On the client side, you can either install Chic through Component:

$ component install rowanmanning/chic

or by simply including chic.js in your page:

<script src="path/to/lib/chic.js"></script>

Usage

In Node.js or using Component, you can include Chic in your script by using require:

var Class = require('chic').Class;

If you're just including with a <script>, Class is available in the chic namespace:

var Class = chic.Class;

The rest of the examples assume you've got the Class variable already.

Create a class

Creating classes is very simple. You extend the base class like this:

var Animal = Class.extend();

Obviously you want to add methods to your class, to give it some functionality:

var Animal = Class.extend({
    eat:   function () { ... },
    sleep: function () { ... },
    poop:  function () { ... }
});

The init method is a special one. This is your class constructor, and is called when a new instance of your class is created. You can set things up in here.

var Animal = Class.extend({
    init: function () {
        this.alive = true;
    }
});

Instantiating a class

Instantiating your new class is just like instantiating any other JavaScript class now. You'll be able to use all those methods you defined!

var fluffy = new Animal();
fluffy.poop(); // Bad Fluffy!

Extending classes

Any class you create is also extendable. You extend custom classes in exactly the same way as the base class:

var Cat = Animal.extend();

If you define methods in this extend, then they will override methods of the same name which have been inherited from the parent class. For example:

var Animal = Class.extend({
    speak: function () {
        return 'Roar!';
    }
});

var Cat = Animal.extend({
    speak: function () {
        return 'Miaow?';
    }
});

var mrTibbles = new Cat();
mrTibbles.speak(); // Miaow?

If you wish to call the parent method, then that's possible using this.sup, which is a reference to the parent method with the same name as the one being called:

var Animal = Class.extend({
    init: function (name) {
        this.name = name;
    },
    eat: function () {
        return this.name + ' is eating';
    }
});

var Cat = Animal.extend({
    eat: function () {
        return this.sup() + ' like a good kitty';
    }
});

var pet = new Cat('Mr Tibbles');
pet.eat(); // Mr Tibbles is eating like a good kitty

Development

To develop Chic, you'll need to clone the repo and install dependencies:

$ npm install

No code will be accepted unless all tests are passing and there are no lint errors. Commands are outlined below:

Lint code

Run JSHint with the correct config against the code-base:

$ npm run-script lint

Run unit tests (CLI)

Run unit tests on the command line in a Node environment:

$ npm test

Run unit tests (browser)

To run unit tests in supported browsers, you need to run a small express app to serve the files (this bundles test together to make managing them a lot easier):

$ npm run-script testapp

Now you will be able to visit http://localhost:3893/ in your browsers to run the tests. The app will automatically restart whenever a JavaScript file changes locally, so re-running the tests is just a case of reloading the page.

Unfortunately, my testing tools don't work correctly in Firefox 3.6 and IE 6–8. Because of this, there is a stripped down test suite available on http://localhost:3893/legacy which caters for these browsers.

Credit

This library was inspired by John Resig's great Simple JavaScript Inheritance post.

License

Chic is licensed under the MIT license.