Book Review: Regular Expressions Cookbook By Jan Goyvaerts and Steven Levithan

Regular expression is always a tricky subject for programmers and sysadmins. When you are dealing with lot of text handling, understanding how to use Reg-ex effectively is essential. It is hard to remember the syntax of reg-ex on top of your head all the times.

Regular Expressions Cookbook is written by the Reg-Ex Jedi Master Jan Goyvaerts along with Steven Levithan.

This book with ISBN-10: 0596520689 and ISBN-13: 978-0596520687 was published by O’reilly in May 2009 and has a total of 510 pages.

Regular Expression Flavors

Following regular expression flavors are covered in this book:

• Perl: Version 5.6, 5.8 and 5.10 are covered.
• PCRE: Perl-Compatible Regular Expressions. Covers PCRE V4 – V7.
• Java
• Javascript
• .NET
• Python
• Ruby

Replacement Text Flavors

Following replacement text flavors are covered in this book:

• Perl – s/regex/replace/
• PHP – preg_replace
• .NET – System.Text.RegularExpressions
• Java – java.util.regex
• Javascript
• Python – re module with sub function
• Ruby

100+ Recipe Ingredients

This cook book has over 100 recipes. Each recipe has the following:

• Problem Definition. (i.e the real-world reg-ex requirement)
• Solution in all flavors
• Examples in a specific programming language. This includes a detailed explanation of what is going behind the scenes in the regular expression.

There are total of 8 chapters in this cook book. I’ve given some high level information of what is covered in each and every chapter.

Chapter 1: Introduction to Regular Expressions

This chapters gives a high level introduction to regular expression explaining the search and replace concepts. This also explains the various utilities that are required to work with regular expressions.

Chapter 2: Basic Regular Expression Skills

Before jumping into the real world problems and solutions, this chapter explains the technical details on some of the fundamentals of regular expressions. For example:

• How to match something at the start/end of the line
• Insert match context into the replacement text.

Chapter 3: Programming with Regular Expressions

Contains recipes of how to implement various regular expressions in the programming languages that you are using. For example:

• Importing regular expression library
• Creating regular expression objects

Chapter 4: Validation and Formatting

This is an awesome chapter that contains lot of real-world examples on how to validate tons of different user inputs. For example:

• Email Address Validation
• Phone Numbers (US and International) Validation
• Date and Time Format Validation
• Alphanumeric Validation
• Postal/Zip Code Validation (US, Canada, UK)
• Credit Card Number validation

Chapter 5: Words, Lines, and Special Characters

This chapter contains recipes for intensive text manipulations. For example:

• Find Specific Word
• Find All Except Specific Word
• Remove Duplicate Lines
• Replace Repeated Whitespace with a Single Space

Chapter 6: Numbers

It is very tricky to manipulate numbers inside a regular expression. This chapter explains some basic number manipulation. For example:

• Manipulate Integer, Hex and Binary
• Strip Leading Zeros
• Manipulate Roman Numerals

Chapter 7: URLs, Paths, and Internet Addresses

This is one of my favorite chapters. This chapter is full of practical recipes for sysadmins.

• Convert URL to Links
• Validate URL
• Extract Scheme, User, Host Name, Port Number, Path, Query, Fragment from URL
• Validate Domain Name
• Match IPv4, IPv6 Address
• Strip Invalid characters from Filenames

Chapter 8: Markup and Data Exchange

Explains about regular expression manipulating while dealing with HTML, XHTML, XML,CSV and INI files. For example:

• Replace <b> with <strong> in HTML
• Convert plain text to HTML
• Match INI Name-Value Pairs

Geek Rating: 5/5 Stars

Regular Expressions Cookbook is Highly Recommended. This is hands-down the best book on the regular expression written by the Reg-Ex guru Jan Goyvaerts himself. Sysadmins and DBAs who write administrative scripts in Perl should definitely have this book as a reference. This is a must-have for programmers of all languages. When you have this book in your desk, regular expression will not look intimidating at all.