Regular Expressions Cookbook

Chapter 3. Programming with Regular Expressions

Programming Languages and Regex Flavors

This chapter explains how to implement regular expressions with your programming language of choice. The recipes in this chapter assume you already have a working regular expression at your disposal; the previous chapters can help in that regard. Now you face the job of putting a regular expression into your source code and actually making it do something.

We’ve done our best in this chapter to explain exactly how and why each piece of code works the way it does. Because of the level of detail in this chapter, reading it from start to finish may get a bit tedious. If you’re reading Regular Expression Cookbook for the first time, we recommend you skim this chapter to get an idea of what can or needs to be done. Later, when you want to implement one of the regular expressions from the following chapters, come back here to learn exactly how to integrate the regexes with your programming language of choice.

Chapters 4 through 8 use regular expressions to solve real-world problems. Those chapters focus on the regular expressions themselves, and many recipes in those chapters don’t show any source code at all. To make the regular expressions you find in those chapters work, simply plug them into one of the code snippets in this chapter.

Because the other chapters focus on regular expressions, they present their solutions for specific regular expression flavors, rather than for specific programming languages. ...