Programming Ruby: The Pragmatic Programmers' Guide

James Edward Gray II writes " Programming Ruby: The Pragmatic Programmers' Guide (Second Edition), known as the Pickaxe II to its fans, is an extremely current view of the Ruby programming language. Revised primarily by Dave Thomas, a founding father of the English Ruby community, Programming Ruby is distilled expertise from a reliable source. In the past, quality English documentation of Ruby has been in short supply, but if any one volume could solve that problem, this is it." Read on for the rest of Gray's review. Programming Ruby: The Pragmatic Programmers' Guide author Dave Thomas with Chad Fowler and Andy Hunt pages 830 publisher Pragmatic Bookshelf rating 9 reviewer James Edward Gray II ISBN 0974514055 summary The definitive source for all things Ruby.

If you're not familiar with it, Ruby is a very fun and elegant scripting language that has been described as "more powerful than Perl and more object oriented than Python." I won't start a language war by defending that statement, but I will tell you what makes Ruby very attractive to me: Extremely object oriented, super clean syntax, and a smooth blending of iterators and code blocks for straightforward, concise solutions. If that sounds like a language you would like to know more about, Programming Ruby is the book for you.

At 830 pages, this edition is considerably larger than the first. It represents an expansion on many topics originally covered, in addition to all new coverage on topics like unit testing, RDoc documentation for Ruby source code, and more. Better still, "Duck Typing," a topic central to Ruby philosophy, receives its own enlightening chapter. This volume covers the very latest release of the language, often highlighting new features and even giving tips for things to watch for in future versions.

Programming Ruby is divided into four distinct sections. "Part I - Facets of Ruby" is a tutorial on the Ruby Programming Language. It's very effective, but I probably better give a warning here: This book teaches you how to program in Ruby, not how to program. You likely won't feel comfortable, even in this tutorial section, unless you have some experience with other programming languages. As an example, Ruby is object oriented on a scale with languages like Smalltalk, so you'll need to know object oriented programming. This book makes no attempt to teach such concepts, excepting how they apply to Ruby. As long as you come with the proper background, this section will get you on your feet with Ruby in under 200 pages. It's very well thought out.

"Part II - Ruby in its Setting" is a mixed-bag tour on the many places Ruby sees use. Web programming, command-line hacking, using TK to build GUIs, and Windows programming are just some of the covered topics. Other chapters in here focus on elements unique to Ruby, like the earlier mentioned RDoc or "irb," the interactive Ruby shell. There's even a chapter in here on package management with RubyGems.

When you're ready, "Part III - Ruby Crystallized" will take you deep into the core of Ruby syntax and functionality. This section tells you all the details about how Ruby reads your code, and how it runs. I think few people could soak in all the tidbits in here in one scan. I've read it twice now and learned about as much both times. There's a lot of great Ruby knowledge waiting to be mined out of here.

Finally, "Part IV - Ruby Library Reference" is the best Ruby reference I've yet run across. It covers every class, module, method and constant in core Ruby. The descriptions for these entities tell you exactly what you need to know, the examples, though short, are inspiring, and the comments sneak in subtle hints that are more than useful. Following this, the book gives an overview of all Standard Libraries included with Ruby. This section really opened my eyes to the tools I've been missing out on simply because I didn't know they were there. Be warned: These Standard Library summaries won't teach you every feature available. They just tell you what they're for so you'll know where to look for the information you need. The last great feature in this section is a terrific index. I care about the index and a book that has a bad one will really bother me. Luckily, that couldn't be further from the truth here.

Programming Ruby isn't perfect, of course. Some of the chapters are not as thorough as you wish they could be, simply because of the amount of information that needs to be covered. The chapter on threads is probably the biggest example of this, but remember that entire volumes have been written on threading. Another minor point is that some of the examples are quite contrived. This bothers some people, but I don't feel it's too much trouble for the book's target audience. As I've said, you're expected to know how to program going into this book, just not how to program in Ruby.

Programming Ruby at least touches on most things central to the Ruby Programming Language, and goes into considerable detail more often than not. There's something for all levels here. You can learn Ruby from the tutorial, as I did with the first edition, but you'll keep coming back to the wonderful reference and to go deeper into specific areas of interest. That's a lot of great mileage for one book. I'm willing to bet most Ruby Gurus keep it in arm's reach, because Ruby wouldn't be half as much fun without it.

You can purchase Programming Ruby from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Comments

Re:What demand is there for RUBY in the workplace?

[Rich_Kilmer]

We have built an extremely robust distributed testing framework for a Java-based multi-agent system completely implemented in Ruby (see Cougaar for more on the project and the ACME testing framework). We were told on starting this project (at DARPA) that it would never work...I really like proving people wrong ;-) My company is using its Ruby expertise as a differentiator in the market and getting very good reception.

Re:Too many new languages at once...

[cmowire]

No, there is a difference. It's a mistaken notion that Ruby is like Python meets Perl.

It's more like Smalltalk + Regular Expression + Incidental Other Goodies + Culture.

I've tried both, and I like Ruby far more than Python. Ruby is an incredible language that tends to enable really simple, yet sophisticated code. When people talk about the Ruby Way, they aren't kidding. Ruby is endearing to me in ways that Python never was.

Ruby and Python are both drinking from the smalltalk fountain, but they are still very different. Ruby plows head-on into more functional-programming types of paradigms while still using objects.

Re:Too many new languages at once...

[xteddy]

You don't have list comprehensions in SML. Last time I checked, this was still a functional language.
The comp.lang.functional FAQ says

Functional programming is a style of programming that emphasizes the evaluation of expressions, rather than execution of commands. The expressions in these language are formed by using functions to combine basic values. A functional language is a language that supports and encourages programming in a functional style.

Actually Ruby only has expressions, so it seems to be a pretty good candidate. You can also create functional objects and use them as arguments:

def add(x, y) x + y end

(1..10).inject &method(:add) # => 55

The same in Common LISP, also a functional programming language:

(defun add(x y) (+ x y))

(reduce #'add (list 1 2 3 4 5 6 7 8 9 10)) ; => 55

Doesn't look so different, does it?

Re:Syntactically significant whitespace

[dozer]

Ever notice that there's tons of Perl, PHP, and Ruby snippents all over the web but very few Python snippets? It's because you really can't copy Python from the browser and paste it into a text editor! The whitespace gets changed and the program breaks in very hard-to-diagnose ways. It's rather funny.

There are many features of Python that will be adopted by future languages, but I doubt that significant whitespace is among them.