Mastering Regular Expressions

If you don't use regular expressions yet, you will discover in this book a whole new world of mastery over your data. If you already use them, you'll appreciate this book's unprecedented detail and breadth of coverage. If you think you know all you need to know about regular expressions, this book is a stunning eye-opener.

As this book shows, a command of regular expressions is an invaluable skill. Regular expressions allow you to code complex and subtle text processing that you never imagined could be automated. Regular expressions can save you time and aggravation. They can be used to craft elegant solutions to a wide range of problems. Once you've mastered regular expressions, they'll become an invaluable part of your toolkit. You will wonder how you ever got by without them.

Yet despite their wide availability, flexibility, and unparalleled power, regular expressions are frequently underutilized. Yet what is power in the hands of an expert can be fraught with peril for the unwary. Mastering Regular Expressions will help you navigate the minefield to becoming an expert and help you optimize your use of regular expressions.

Mastering Regular Expressions, Third Edition, now includes a full chapter devoted to PHP and its powerful and expressive suite of regular expression functions, in addition to enhanced PHP coverage in the central "core" chapters. Furthermore, this edition has been updated throughout to reflect advances in other languages, including expanded in-depth coverage of Sun's java.util.regex package, which has emerged as the standard Java regex implementation.Topics include:

• A comparison of features among different versions of many languages and tools
• How the regular expression engine works
• Optimization (major savings available here!)
• Matching just what you want, but not what you don't want
• Sections and chapters on individual languages

Written in the lucid, entertaining tone that makes a complex, dry topic become crystal-clear to programmers, and sprinkled with solutions to complex real-world problems, Mastering Regular Expressions, Third Edition offers a wealth information that you can put to immediate use.

Reviews of this new edition and the second edition:

"There isn't a better (or more useful) book available on regular expressions."
--Zak Greant, Managing Director, eZ Systems

"A real tour-de-force of a book which not only covers the mechanics of regexes in extraordinary detail but also talks about efficiency and the use of regexes in Perl, Java, and .NET...If you use regular expressions as part of your professional work (even if you already have a good book on whatever language you're programming in) I would strongly recommend this book to you."
--Dr. Chris Brown, Linux Format

"The author does an outstanding job leading the reader from regex novice to master. The book is extremely easy to read and chock full of useful and relevant examples...Regular expressions are valuable tools that every developer should have in their toolbox. Mastering Regular Expressions is the definitive guide to the subject, and an outstanding resource that belongs on every programmer's bookshelf. Ten out of Ten Horseshoes."
--Jason Menard, Java Ranch

I am a Perl/CGI programmer, and I had considered myself good at RegExp even before I read this book. Most of the things I knew were from Programming Perl, 3rd edition (chapter 5, Pattern Matching). But I still decided to give Jeffrey a chance since I was having some trouble with my Parse::Syntax module, which is designed to parsing *any* programming language and highlighting the syntax accordingly (provided it has a syntax/grammer file written for the specific language). The accuracy of the parser (and more importantly the speed) does depend on well crafted regular expressions.

As I started reading the book, I couldn't stop. I took it to my school's cafeteria with me and no one could make me leave untill I finished the whole book. I was excited. I was pleased! Here is the outline of tha chapters:

Chapter 1 and 2 introduce you to regular expressions and give some basic regex examples. Mail utility and date matching is two of them.

Chapter 3 mostly talks about conventions that all the regex tools follow and their differences.

Chapter 4 deals with Traditional NFA, POSIX NFA and DFA regex engines and their pros and cons. What you'll like the most is the details provided by the author on each and every single example. He also uses a lot of step-by-step illustrations to take you deeper into the regex engine itself and see/feel how it works. He shows the point of backtrackings and provides awesome benchmarks. He uses such examples of matching a quote, allowing escaped quotes inside the pattern, matching C-style comments, IP addresses and many more.

Chapter 5 deals with writing efficient regular expressions for NFA engines. It also re-vists some of the examples provided in the previous chapter and fine-tunes them.

Chapter 6 and 7 deals with Tool-Language specific features of Regex engines. Chapter 6 is dedicated to Awk, Tcl and GNU Emacs, whereas chapter 7 is entirely dedicated to Perl, good over 100 pages of Perlism.

It's true that there're features that Perl 5.6 offers when it comes to regex that didn't exist at the time this book went to press, (lookbehinds, for example). But this no way makes this book dated. Just take my word for it. Jeffrey put together a great masterpiece that will not die for many years, no matter how fast the technology tends to enhance
Haven't read anything more exciting than this for many years.


RE: Third Edition   August 21, 2006
Brett Merkey (Palm Harbor, FL United States)
17 out of 18 found this review helpful


The third edition just came out -- and that makes 10 years since this book was first published. That statistic alone indicates the steady value of "Mastering Regular Expressions" across the constant changes in applied software technology over that time. Regular expressions, still the most under-used power tool, needs a book like this.

Specifically, this third edition features enhanced coverage of PHP in the early tutorial chapters, plus an all new chapter devoted entirely to PHP regular expressions.

Also new in this edition, the Java chapter has been rewritten and expanded to reflect new features as Java itself has developed.



Eureka!   December 1, 2001
S. Donohue (Allen Park, MI USA)
9 out of 10 found this review helpful

Okay, so maybe I'm no Archimedes, but this book suddenly illuminated the world of regular expressions for me. I'd toiled through three or four other books, some of them pretty good, without getting it.
After just a few chapters of this one, I can finally say that I understand regular expressions and can use them to my advantage instead of just being vaguely aware that there is a better way to do what I've been trying to do.
Don't wait, buy it now!


Invaluable Regex Insights   December 14, 2003
Jack D. Herrington (Silicon Valley, CA)
3 out of 3 found this review helpful

I used, but never truly understood, regular expressions until I read this book. If you use regular expressions in a production setting you need to understand them at a deep level to make sure you won't fall into performance traps. This book provides that deep perspective. The author really knows his stuff and is able to communicate it effectively. Another O'Reilly classic.


Good geek book   September 30, 2004
Vincent Poirier (Tokyo, Japan)
1 out of 1 found this review helpful

Mastering Regular Expressions is for many people including among others casual users, system administrators, and programmers. Only programmers will understand (or need) the whole book, but people with only a tiny little Perl or Unix knowledge will gain much from the first few chapters. The RegEx book is useful as a primer to go a little beyond the usual wild card (i.e. '*') when searching text files for something, it's useful for systems administrators who need to write task automation scripts, and it offers Perl, Java, and .NET programmers a complete reference to the RegEx engines they need to understand to optimize their code.

And if they don't already have it, this will make a great present for your techno geek other half. They'll be impressed...