emberjs/ember.js — pull request #2459 by teddyzeenny (2013-04-12 18:07:43+00:00)
Title: Include useful exception when accessing DS without ember-data

I've stumbled upon several SO questions similar to "What does DS is not defined mean?".

This throws an exception explaining to the user that they need to include Ember Data and to download it from http://s3.amazonaws.com/builds.emberjs.com/ember-data-latest.js

I thought it could improve the getting started experience.