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Masked input plugin angular.js adapter and JS comma operator

I was recently adapting jQuery masked input plugin (http://digitalbush.com/projects/masked-input-plugin) for angular.js. This is the adapter itself:

In order to produce the adapter, it was necessary to familiarize myself with source code of the original library. It was a very interesting task indeed!

While the library works very well, it's source code is ... a bit too smart. It's uncompressed version looked a bit like it was compressed. But what was really interesting about it was how JavaScript comma operator was a bit abused. This lead me to research the topic a bit and I've found an amazing write-up on the topic, which I really recommend to read: http://javascriptweblog.wordpress.com/2011/04/04/the-javascript-comma-operator/

UPDATE: I should have researched it better. The link at the project site really does point to some semi-minified source code. The source code at github (https://github.com/digitalBush/jquery.maskedinput) looks much more readable!
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