pwfoo / namespace.js

A simple namespace function for JavaScript.

namespace.js

A simple namespace function for JavaScript.

Background

To organise code into logical groups, programming languages such as Java and C# have the concept of a namespace.

JavaScript does not have the concept of namespaces - but similar functionality can be created. Namespace.js does just that.

Why?

In some of JavaScript's module patterns, it is often recommended to organise these modules into some kind of a custom namespace to reduce global clutter:

// Create a namespace called 'Animal'
var Animal = window.Animal || {};

Animal.Cat = {
    speak: function() {
    	return 'Meow!';
    }
};

Animal.Cat.speak(); // "Meow!"

For longer namespaces, the code for creating the custom namespace can quickly become ugly and unwieldy:

// Create a namespace called 'Animal.Mammal.Feline'
var Animal = window.Animal || {};
Animal.Mammal = window.Animal.Mammal || {};
Animal.Mammal.Feline = window.Animal.Mammal.Feline || {};

Animal.Mammal.Feline.Cat = {
    speak: function() {
    	return 'Meow!';
    }
};

Animal.Mammal.Feline.Cat.speak(); // "Meow!"

In the snippet above, the top 3 lines of code are ugly and repetative. Namespace.js aims to clean up the process of defining the custom namespace:

namespace('Animal.Mammal.Feline');

Animal.Mammal.Feline.Cat = {
    speak: function() {
    	return 'Meow!';
    }
};

Animal.Mammal.Feline.Cat.speak(); // "Meow!"

Usage (browser)

1. Include namespace.js in your HTML:

<script src="namespace.js"></script>

2. Define and then extend a namespace in your JavaScript:

namespace('Animal.Mammal.Feline');

Animal.Mammal.Feline.Cat = {
    speak: function() {
    	return 'Meow!';
    }
};

3. Call your namespaced JavaScript code from elsewhere:

Animal.Mammal.Feline.Cat.speak(); // returns 'Meow!'

// or

var cat = Animal.Mammal.Feline.Cat;
cat.speak(); // returns 'Meow!'

Modules? Self-executing functions?

Namespace.js does not care what you do with the namespace. It doesn't matter if you use a fancy JavaScript module pattern, or wrap all or none of your code in a self-executing function.

All namespace.js does is create the namespace in a readable and concise manner.

Usage (Node.js)

Currently, namespace.js will not work in Node because window is referenced in both the source and the spec files. I am sure this is trivial to fix, but I have not gotten round to it yet since I made this and used it within the context of a browser, not a Node app.