Preface

Over a decade ago (nearly eternity in Internet Time), Randal Schwartz wrote the first edition of Learning Perl. In the intervening years, Perl itself has grown substantially from a "cool" scripting language used primarily by Unix system administrators to a robust object-oriented programming (OOP) language that runs on practically every computing platform known to mankind.

Throughout its four editions, Learning Perl remained the same size (about 300 pages) and continued to cover much of the same material to remain compact and accessible to the beginning programmer. But there is much more to learn about Perl now than when that first book was written.

Randal called the first edition of this book Learning Perl Objects, References, and Modules, and now it's Intermediate Perl, but we like to think of it as just Learning More Perl.^[*] This is the book that picks up where Learning Perl leaves off. We show you how to use Perl to write larger programs.

^[*] Don't ask why it isn't called that. We must have had 300 emails on the subject. Okay, ask, since we know you're going to anyway. You never really stop learning Perl, so Learning More Perl doesn't really tell you much about the book. Our editor chose the name, which tells you what to expect.

As in Learning Perl, we designed each chapter to be small enough to read in just an hour or so. Each chapter ends with a series of exercises to help you practice what you've just learned, and the answers are in the appendix for your reference. And like Learning Perl, we've developed the material in this book for a teaching environment and used it in that setting, including for our own use at Stonehenge Consulting Services, as we conduct on-site and open-enrollment trainings.

You don't have to be a Unix guru, or even a Unix user, to benefit from this book. Unless otherwise noted, everything in this book applies equally well to Windows ActivePerl from ActiveState and all other modern implementations of Perl. To use this book, you just need to be familiar with the material in Learning Perl and have the ambition to go further.