Programming Perl (3rd Edition)

"Programming Perl" is not just a book about Perl. It is also a unique introduction to the language and its culture, as one might expect only from its authors. Larry Wall is the inventor of Perl, and provides a unique perspective on the evolution of Perl and its future direction. Tom Christiansen was one of the first champions of the language, and lives and breathes the complexities of Perl internals as few other mortals do. Jon Orwant is the editor of

"The Perl Journal," which has brought together the Perl community as a common forum for new developments in Perl.

Any Perl book can show the syntax of Perl's functions, but only this one is a comprehensive guide to all the nooks and crannies of the language. Any Perl book can explain typeglobs, pseudohashes, and closures, but only this one shows how they really work. Any Perl book can say that "my" is faster than "local," but only this one explains why. Any Perl book can have a title, but only this book is affectionately known by all Perl programmers as "The Camel."

This third edition of "Programming Perl" has been expanded to cover version 5.6 of this maturing language. New topics include threading, the compiler, Unicode, and other new features that have been added since the previous edition.

Like Topsy, Perl just grew, and as a result the need for a third edition came about. It's now over 1,000 pages, which it needs to be, as it performs several different duties. First, it's an introduction to the Perl language for those who are new to programming; also, it's a guide for those who are coming from other languages; and, finally, it's a Perl language reference.

Among Larry Wall's other pursuits is being a linguist, and it's perhaps for this reason that Perl is a peculiarly flexible language with many routes to achieving the same ends, as the authors ably demonstrate. It's also extensible in several ways, designed to work with many other languages. Also, as it's largely interpreted, programs written in Perl tend to run unmodified on a variety of platforms--although platform-specific Perl modules and programming practices are also discussed.

A major strength of Programming Perl is the way subject areas are approached from several directions. This constant shift of viewpoint eliminates blind spots in the reader's understanding and provides a pleasing echo of the way Perl itself can take many routes from here to there.

Because the Perl community is both knowledgeable and active, the language covers much more ground here than in the previous edition. Even if you have both previous editions, you'll want this latest version--if only for the new jokes. --Steve Patient, amazon.co.uk