Javascript Generators are AWESOME. At first glance, they seem overly simple and not very useful, but with a little bit of library love, they turn your async javascript from awful to joyful.
View the code here: https://gist.github.com/learncodeacademy/bf04432597334190bef4
If you don't know promises, watch this video: http://www.youtube.com/watch?v=obaSQBBWZLk
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