Klassy.js

A class system for JavaScript featuring mixins, constructors, and superclass access.

Extracted from Orbit.js.

Usage

Either define your own base class with defineClass or use the built-in base class Klass.

Any classes can be extended via the extend method.

Klass

A base class that can be extended.

var CelestialObject = Klass.extend({
  init: function(name) {
    this._super();
    this.name = name;
    this.isCelestialObject = true;
  },
  greeting: function() {
    return 'Hello from ' + this.name;
  }
});

var Planet = CelestialObject.extend({
  init: function(name) {
    this._super.apply(this, arguments);
    this.isPlanet = true;
  },
  greeting: function() {
    return this._super() + '!';
  },
});

var earth = new Planet('Earth');

console.log(earth instanceof Klass);           // true
console.log(earth instanceof CelestialObject); // true
console.log(earth instanceof Planet);          // true

console.log(earth.isCelestialObject);          // true
console.log(earth.isPlanet);                   // true

console.log(earth.greeting());                 // 'Hello from Earth!'

defineClass

Define a new class with the properties and methods of one or more other classes.

The new class can be based on a SuperClass, which will be inserted into its prototype chain.

Furthermore, one or more mixins (object that contain properties and/or methods) may be specified, which will be applied in order. When a method is replaced with another method, it will be wrapped in a function that makes the previous method accessible via this._super.

defineClass(SuperClass [, mixins, ...])

• SuperClass - A base class to extend. If mixins are to be included without a SuperClass, pass null for SuperClass.
• mixins - One or more objects that contain properties and methods to apply to the new class.

extendClass

Extend a class with the properties and methods of one or more other classes.

When a method is replaced with another method, it will be wrapped in a function that makes the replaced method accessible via this._super.

extendClass(destination [, source, ...])

• destination - The class to merge into
• source - One or more source classes

License

Copyright 2014-2015 Cerebris Corporation. MIT License (see LICENSE for details).