Backbone.js requires json2.js?

backbone.js, javascript

Solution

json2.js provides `JSON.parse` and `JSON.stringify` functions, which Backbone depends on. They've been included in browsers for a while but it's probably listed in case your environment doesn't include it, or you want a consistent implementation in your app.

Problem

From the site: Backbone's only hard dependency is either Underscore.js ( > 1.4.3) or Lo-Dash. For RESTful persistence, history support via Backbone.Router and DOM manipulation with Backbone.View, include json2.js, and either jQuery ( > 1.4.2) or Zepto. Why is json2.js mentioned? I have run my app in ie7-9 among other browsers without requiring this file and it works. Is this a performance thing?

Original source