This book is a collection of 70 articles from The Perl Journal, assembled by TPJ's editor, Jon Orwant.

This is an unusual book, in the sense that it's not one continous whole, but rather a collection of unrelated articles you can (in theory) read in any order.

The articles in the book are divided into eight parts:

Part I. Beginner Concepts: the basic stuff of Perl. Not much to learn here even for a reasonably seasoned, but beginners may find this part interesting.

Part II. Regular Expressions: a very interesting part, with 5 articles dealing with the inner workings of regular expressions in Perl (and in general). Very informational for a deeper understanding of this important topic.

Part III. Computer Science: the best part in the book, in my opinion. The articles about Infinite Lists, Memoization and Parsing are particularly excellent.

Part IV. Programming Techniques: an interesting part about various advanced techniques in Perl programming - closures, source filters, overloading, etc. Experienced Perl hackers may know most of what's written there, but still it's a good refresher and a reminder of the various tools in the hands of the programmer.

Part V. Software Development, Part VI. Networking, Part VII. Databases: I didn't enjoy these chapters, because it felt like reading a CPAN brochure. I guess it can be good in a monthly magazine, but reading 30 articles in a row about "here's a module I did to do X" where X is quite similar from article to article is daunting.

Part VIII. Internals: again, an excellent part. I especially liked the description of Perl's lexical analysis. There's no doubt the Perl interpreter is one complex beast, and getting a glimpse into it is very interesting.

There's a gotcha with reading books like this. Being a collection of articles taken from various magazine releases they are extracted from their "natural" context and may fit not so well together. There's a difference between reading a Perl article once a month and reading a whole bunch of them consecutively. And still, some of the articles deal with very interesting topics and are written extremely well, they're a pleasure to read even in the context of 70 other articles.