Foreword

Do you know why experienced Ruby programmers tend to reach for basic collections and hashes while programmers from other languages go for more specialized classes? Do you know the difference between strip, chop, and chomp, and why there are three such similar methods when apparently one might suffice? (Not to mention lstrip and rstrip!) Do you know the downsides of dynamic typing? Do you know why the differences between strings and symbols get so blurry, even to experienced Ruby developers? How about metaprogramming? What the heck is an eigenclass? How about protected methods? Do you know what they’re really about? Really? Are you sure?

Russ knows all that stuff and more. And if books are like babies, then Russ is that experienced mom who pops out her second child after a couple of hours of labor and is back at work a week later in her pre-pregnancy clothes as if nothing out of the ordinary happened. You know: the one all the other moms talk about in hushed tones of disbelief and reverence. That’s the way my series authors discuss Russ.

Not that there’s anything small or insignificant about Russ’ bouncing new baby . . . eh, I mean book. On the contrary, weighing in at just over 400 pages, this tome is slightly larger than its older sibling Design Patterns in Ruby. The family resemblance is crystal clear: Russ is first and foremost your friend. His approachable writing style makes even the driest Ruby language topics engaging and funny. Like the way that symbols remind Russ “of the eyes peering out from the tilted head of a confused but friendly dog.”

Truth is, we need this kind of book now more than ever. Ruby has hit the mainstream with the force of a Hulk Smash, and the masses are paddling along well-known routes without full (heck, sometimes any) understanding of what makes their favorite frameworks and library APIs so vibrant and navigable. So for those not content with the basics, those who want to go beyond shallow understanding, this book goes deep. It helps readers achieve true mastery of Ruby, a programming language with some of the deepest, darkest pools of nuance and texture of all the major languages of modern times.

I know you’re going to enjoy this book, just like I did. And if you do, please join me in encouraging Russ to get knocked up again soon.

—Obie Fernandez, Professional Ruby Series Editor