Regular Expressions Cookbook, 2nd Edition

Chapter 7. Source Code and Log Files

As shown in Construct a Parser, regular expressions are an excellent solution for tokenizing input while constructing a parser for a custom file format or scripting language. This chapter has many recipes for matching syntactic elements that are commonly used in programming languages and other text-based file formats. You can combine the regular expressions from these recipes into a larger regular expression to be used by a parser. These regular expressions will also come in handy when manipulating source code in a text editor and when searching through your code base with a grep tool.

The second part of this chapter shows how you can use regular expressions to extract information from log files. The recipes mostly deal with web logs, as many of our readers will have access to such log files and may even be familiar with their format. You can easily adapt the techniques shown in these recipes to any other log formats you may be dealing with.