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Programming Ruby 1.9, 3rd Edition

Dave Thomas, Chad Fowler, Andy Hunt

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Ruby is the fastest growing and most exciting dynamic language out there. If you need to get working programs delivered fast, you should add to your toolbox. This book is the only complete reference for Ruby 1.9, the very latest version of Ruby. (If you are still using Ruby 1.8, you'll want to check out the original PickAxe.)