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@zhuochun zhuochun/Backbone.js
Created Oct 22, 2012

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Define JavaScript Frameworks
// Initial Setup
// -------------
// Save a reference to the global object (`window` in the browser, `exports`
// on the server).
var root = this;
// Save the previous value of the `Backbone` variable, so that it can be
// restored later on, if `noConflict` is used.
var previousBackbone = root.Backbone;
// The top-level namespace. All public Backbone classes and modules will
// be attached to this. Exported for both CommonJS and the browser.
var Backbone;
if (typeof exports !== 'undefined') {
Backbone = exports;
} else {
Backbone = root.Backbone = {};
// Current version of the library. Keep in sync with `package.json`.
Backbone.VERSION = '0.9.2';
(function(window, undefined) {
// Map over jQuery in case of overwrite
var _jQuery = window.jQuery,
// Map over the $ in case of overwrite
_$ = window.$,
// Define a local copy of jQuery
jQuery = function( selector, context ) {
// The jQuery object is actually just the init constructor 'enhanced'
return new jQuery.fn.init( selector, context, rootjQuery );
jQuery.fn = jQuery.prototype = {
constructor: jQuery,
init: function() {
// Expose jQuery to the global object
window.jQuery = window.$ = jQuery;
// Expose jQuery as an AMD module, but only for AMD loaders that
// understand the issues with loading multiple versions of jQuery
// in a page that all might call define(). The loader will indicate
// they have special allowances for multiple jQuery versions by
// specifying define.amd.jQuery = true. Register as a named module,
// since jQuery can be concatenated with other files that may use define,
// but not use a proper concatenation script that understands anonymous
// AMD modules. A named AMD is safest and most robust way to register.
// Lowercase jquery is used because AMD module names are derived from
// file names, and jQuery is normally delivered in a lowercase file name.
// Do this after creating the global so that if an AMD module wants to call
// noConflict to hide this version of jQuery, it will work.
if ( typeof define === "function" && define.amd && define.amd.jQuery ) {
define( "jquery", [], function () { return jQuery; } );
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