Programming Ruby 1.9 (3rd edition)

If you are an experienced Ruby programmer, you will undoubtedly have read, or browsed, some version of Dave Thomas’s Programming Ruby, popularly known as the ‘Pickaxe Book’ thanks to the image on its cover.

The first edition, which was based on Ruby 1.6, is available free online. The second edition, was expanded by over 200 pages to cover the features of Ruby 1.8. And the 3rd edition, which has gained another hundred or so pages (960 pages in total), is devoted to Ruby 1.9.

The book is so well-known and highly regarded among Ruby aficionados that it would be superfluous for me to recommend it to experienced Ruby coders. Suffice to say, it provides such compendious documentation of the Ruby languages that, to all intents and purposes, it may be regarded as the definitive description of Ruby. The 3rd edition describes the new and altered features of the Ruby class library and syntax – from significant changes such as the scoping of variables in blocks – to minor changes of the behaviour of specific methods which are indicated by a ‘1.9’ margin note.

While the reference material in the book is invaluable there is also tutorial. This, in my view, may be more easily accessible to users with a sound background in a comparable scripting language, such as Python, than to programmers coming from a background in a mainstream compiled language. For example, I think the section on blocks (introduced as early as page 24) is too much too soon. While blocks are important and powerful, they can be difficult to understand initially and I well recall the problems I had in figuring them out when I was a Ruby-newbie. Other gnarly subjects such as modules and mixins are also dealt with rather too quickly, in my opinion, to hammer home to a Ruby novice how they really work.

But that’s a minor criticism. The real point of this book is not to teach you to program Ruby from scratch – it is to document the Ruby language and class library and to explain how Ruby works. Judged in that light, it is without equal. It remains the essential book for serious Ruby programmers.