How to use the regular expression functions provided by the ‘re’ library to match, search, and replace text in your Python programs. Regular expressions, or “regex,” is a system for finding complex ...

The first time I ever encountered a regular expression was many years ago now, but I still remember my first thoughts on it: What is this string-like thing? I don’t want to touch it, it looks scary. I ...

I'm wearing my regex dunce cap again. I want to return a positive match if I find "this" in a string, but not if I find "this" and also "that" in the string. Put another way: I want to return a ...

Tony Northrup is a developer, security consultant and author with more than 10 years of professional experience developing applications for Microsoft Windows. Developers frequently need to process ...

The String.split methods can be very convenient for easily splitting a provided String based on a provided regular expression String. The only trick is figuring out a regular expression token to use ...

There are times during development when you need to match text against a search phrase. NSString offers a few simple built-in routines that offer basic comparison options. For example, use ...

Regular expressions come in handy for all varieties of text processing, but are often misunderstood–even by veteran developers. Here’s a look at intermediate-level regular expressions and what they ...

Let’s say we need a JavaScript function that will take a string of tagged text (that is, it contains Extensible Markup Language (XML) markup) and return only the tags (and not the text that the tags ...

These are the formal rules for forming basic UNIX regular expressions. For some simple examples, skip to Simple Examples. The rules come from the Solaris 7 regexp(5) manual page. The I2A2 reflector ...

Whether you are parsing logs or validating input, using regular expressions is a great way to accomplish both of these things. The problem is: regular expressions can be hard and that will only grow ...