Regex Guru

Monday, 30 September 2013 Thoroughly Updated

Filed under: The Guru's Kitchen — Jan Goyvaerts @ 10:55

RegexBuddy 4 was released earlier this month. This is a major upgrade that significantly improves RegexBuddy’s ability to emulate the features and deficiencies of the latest versions of all the popular regex flavors as well as many past versions of these flavors.

Along with that, the website has been thoroughly updated with new content. Both the tutorial and reference sections have been significantly expanded to cover all the features of the latest regular expression flavors. There are also new tutorial and reference subsections that explain the syntax used by replacement strings when searching and replacing with regular expressions.

I’m also reviving this blog. In the coming weeks you can expect blog post that highlight the new topics on the website. Later on I’ll blog about more intricate regex-related issues that RegexBuddy 4 emulates but that the website doesn’t talk about or only mentions in passing. RegexBuddy 4.0.0 is aware of 574 different aspects (syntactic and behavioral differences) of 94 regular expression flavors. These numbers are surely to grow with future 4.x.x releases. While RegexBuddy juggles it all with ease, that’s far too much detail to cover in a tutorial or reference that any person would want to read. So the tutorial and reference cover the important features and behaviors, while the blog will serve the corner cases as tidbits. Subscribe to the Regex Guru RSS Feed if you don’t want to miss any articles.

Friday, 28 September 2012

Regular Expressions Cookbook Code Samples

Filed under: Regex Cookbook — Jan Goyvaerts @ 15:15

One of the common criticisms against the first edition was that we
didn’t have the regular expressions and code samples available for download. Since our book only has very short code snippets rather than complete programs, we (the authors) did not have these available as separate files either.

But for the second edition we’re trying to do better. You can now download the code samples from the 2nd edition of Regular Expressions Cookbook. This HTML file contains all the blocks with regular expressions and source code from the book, along with the titles of the chapters, recipes, and sections that they are found in. If you have purchased the book, you can use this file to easily copy and paste the regular expressions and source code snippets.

Even if you purchased the ebook, you may prefer to use this file. The regexes in the ebook are formatted with line breaks and gray dots for spaces to make them easier to read in print. The HTML file does not use such formatting, so you can copy and paste them directly. This means that some very regexes will run beyond the edge of your browser window.

Monday, 3 September 2012

Second Edition of Regular Expressions Cookbook Now In Stock at

Filed under: Regex Cookbook — Jan Goyvaerts @ 15:38

The second edition of Regular Expressions Cookbook is now in stock as a printed book Right now, the printed book is discounted 45% to $27.51, which is actually more than a dollar cheaper than the Kindle edition.

The European Amazon sites don’t have the printed book in stock yet. But it shouldn’t take too long for the book to make it from the US to Europe. They do have the Kindle edition.

Wednesday, 29 August 2012

What’s New in The Second Edition of Regular Expressions Cookbook

Filed under: Regex Cookbook — Jan Goyvaerts @ 9:42

The second edition of Regular Expressions Cookbook is a completely revised edition, not just a minor update. All of the content from the first edition has been updated for the latest versions of the regular expression flavors and programming languages we discuss. We’ve corrected all errors that we could find and rewritten many sections that were either unclear or lacking in detail. And lack of detail was not something the first edition was accused of. Expect the second edition to really dot all i’s and cross all t’s.

A few sections were removed. In particular, we removed much talk about browser inconsistencies as modern browsers are much more compatible with the official JavaScript standard.

There is plenty of new content. The second edition has 101 more pages, bringing the total to 612. It’s almost 20% bigger than the first edition.

We’ve added XRegExp as an additional regex flavor to all recipes throughout the book where XRegExp provides a better solution than standard JavaScript. We did keep the standard JavaScript solutions, so you can decide which is better for your needs.

The new edition adds 21 recipes, bringing the total to 146. 14 of the new recipes are in the new Source Code and Log Files chapter. These recipes demonstrate techniques that are very useful for manipulating source code in a text editor and for dealing with log files using a grep tool.

Chapter 3 which has recipes for programming with regular expressions gets only one new recipe, but it’s a doozy. If anyone has ever flamed you for using a regular expression instead of a parser, you’ll now be able to tell them how you can create your own parser by mixing regular expressions with procedural code. Combined with the recipes from the new Source Code and Log Files chapter, you can create parsers for whatever custom language or file format you like.

If you have any interest in regular expressions at all, whether you’re a beginner or already consider yourself an expert, you definitely need a copy of the second edition of Regular Expressions Cookbook if you didn’t already buy the first. If you did buy the first edition, and you often find yourself referring back to it, then the second edition is a very worthwhile upgrade. You can buy the second edition of Regular Expressions Cookbook from Amazon or wherever technical books are sold. Ask for ISBN 1449319432.

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