This O'Reilly Cookbook provides more than a hundred recipes to help programmers use regular expressions to manipulate text and crunch data. Every programmer needs a grasp of regular expressions, but their power doesn't come without problems--even seasoned users often have trouble tackling performance issues. With recipes for popular programming languages such as C#, Java, javascript, Perl, PHP, Python, Ruby, and VB.NET, this book offers step-by-step solutions to scores of common tasks involving regular expressions.