A few weeks ago I got a review copy of "Practical Ruby Projects: Ideas for the Eclectic Programmers" by Topher Cyll. The main part of the book consists of eight thematic chapters: MIDI music, SVG animation, pocket change problem, turn-based strategy engine, turn-based strategy GUI in Cocoa, genetic algorithms, implementing Lisp in Ruby (what probably got me the review copy), and parsing with RParsec. But don't worry about that, they are only pretexts for demonstrating various genuine issues that you will stumble upon in your Ruby coding and various interesting techniques. In a way the book reads a lot like a typical programming blog, with all the "I had this strange problem while coding something, and I solved it in this incredibly cool way, I hope it's useful to you too" stuff.
The book is very high on code and pretty low on bullshit and beginner filler (which unfortunately plagues so many books these days), so it won't be wasting your time. I was surprised by how many solutions presented in the book were almost identical to what I've done in my projects, like world map implementation in the book's Cocoa app and my jrpg, which uses Python and PyGame/SDL but is surprisingly similar in structure. The part that was most interesting to me was the last chapter with RParsec tutorial, but the book was overall very enjoyable to read.
If you want me to review any other good books, go ahead and send them ;-)
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