Mastering JavaScript

Chapter 5
CarFactory.Sedan = function () {
this.doors = 2;
this.engine_capacity = 2;
};
CarFactory.SUV = function () {
this.doors = 4;
this.engine_capacity = 6;
};
var golf = CarFactory.make('Compact');
var vento = CarFactory.make('Sedan');
var touareg = CarFactory.make('SUV');
golf.info(); //"This car has 4 doors and a 2 liter engine"
We suggest that you try this example in JS Bin and understand the concept by
actually writing its code.
The mixin pattern
Mixins help in significantly reducing functional repetition in our code and help
in function reuse. We can move this shared functionality to a mixin and reduce
duplication of shared behavior. You can then focus on building the actual
functionality and not keep repeating the shared behavior. Let's consider the
following example. We want to create a custom logger that can be used by any object
instance. The logger will become a functionality shared across objects that want to
use/extend the mixin:
var _ = require('underscore');
//Shared functionality encapsulated into a CustomLogger
var logger = (function () {
var CustomLogger = {
log: function (message) {
console.log(message);
}
};
return CustomLogger;
}());
//An object that will need the custom logger to log system
specific logs
var Server = (function (Logger) {
var CustomServer = function () {
this.init = function () {
this.log("Initializing Server...");
};
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