Every time I start to learn a new language, I have fun writing a Cloud App Roulette.
It is a little script that generates Cloud App-like URLs checking if they are valid, to obtain a list of public images and files uploaded by anyone.

I coded my own Cloud App Roulette in Java first, then PHP, Javascript, C and Objective-C. Now I wrote it in Ruby as well, just to keep up :)

With these few lines I learned a lot of useful things:

• different variables’ scope, globals and privates
• map function
• read a status of a page
• multithreading, semaphores and synchronized blocks

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