A big part of what makes Perl/Python/Tcl/Emacs/Vi/
Sed/Awk/Java Servlet/MS Word/etc's text processing abilities
approachable and powerful can be credited to the consistent use of
the regular expressions model and methods of usage.
Regular expressions helps you illustrate to your scripts how to
grab on to interesting landmarks in your documents and what to do
about the nearby text surrounding these landmarks. It is hard to grasp
this old art unless you've been a power user for a while. But
don't panic, this book will help you take advantage of this hidden tool.
This is the first book I purchased when I decided to start learning
Perl. It's the way to go if you already know a little Perl and use
unix tools day in and day out. "Regular expressions" (regex) are
quite important. Since we all want to do the complex things with regex
from each of the above listed scripting environments, its nice to know
that there's a book that will explain to you just exactly how regex
differ in each environment. I think it is a really detailed reference
and will serve as a great tutorial.
Here's another book review:
At Web Nerd Bookshelf (http://www.arsdigita.com/asj/bookshelf) by Philip Greenspun (philg@mit.edu) Philip gave a review for the book:
Since the only thing that a Web nerd can usefully do with Perl is
grind over a bunch of HTML files and touch them up, what you need
most is Mastering Regular Expressions (Friedl; O'Reilly). It is
tough to believe that two pages of manual could be expanded into a
342-page book, but there you have it. This book explains the one
genius feature of Perl: non-greedy *. It makes matching stuff
inside HTML tags about 100 times easier.