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@jammycakes
Last active Dec 19, 2015
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Provides the ability to define namespaces in JavaScript.
/* ====== namespace.js ====== */
// Provides the ability to define namespaces in JavaScript.
/**
* Declares a namespace in JavaScript.
*
* This function can be called in one of two ways:
*
* namespace(ns, obj)
* Declares a namespace, by ensuring that a global variable called ns exists,
* and appending all the properties of obj to it.
*
* namespace(ns, [usings], fn)
* Declares a namespace, by ensuring that a global variable called ns exists,
* and calls fn passing it the arguments in usings.
*/
function namespace(ns) {
"use strict";
var path = ns.split('.');
var target = window;
for (var i = 0; i < path.length; i++) {
var part = path[i];
if (target.hasOwnProperty(part)) {
target = target[part];
}
else {
target = target[part] = {};
}
}
var args, obj;
switch (arguments.length) {
case 1:
return target;
case 2:
args = [];
obj = arguments[1];
break;
default:
args = arguments[1];
obj = arguments[2];
break;
}
if (typeof obj === "function") {
obj = obj.apply(target, args);
}
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
target[key] = obj[key];
}
}
return target;
}
# An example of how to declare a namespace using namespace.js and CoffeeScript
namespace "My.Namespace", [jQuery], ($) ->
# To add a function to a namespace, simply assign it to a property of this
@showMessage = (msg) ->
$('#message').html(msg).show()
# Can also do this with classes
@Message = class Message
constructor: (@msg) ->
show: ->
$('#message').html(msg).show()
/*
* An example of how to declare a namespace using namespace.js
*/
namespace("My.Namespace", [jQuery], function($, undefined) {
"use strict";
/*
* To add a function to a namespace, simply assign it to a property of this
*/
this.showMessage = function(msg) {
$('#message').html(msg).show();
};
});
My.Namespace.showMessage('Hello world');
/*
* How to declare circular references between namespaces.
* This is not a good idea if you can avoid it, but if you need to,
* this is how you do it.
*
* Calling namespace(namespaceName) without a defining function ensures
* that the namespace object exists, and returns a reference to it.
*/
namespace ("My.First.Namespace",
[jQuery, namespace("My.Other.Namespace")],
function ($, other) {
/* whatever */
});
namespace ("My.Other.Namespace",
[jQuery, namespace("My.First.Namespace")],
function ($, first) {
/* whatever */
});
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