If you consider yourself a good cook, you may or may not know how to make a souffle or baklava. But there are certain things you probably do know how to do that form the basis of many recipes. For ...

When working with text or CSV data in Python, you may find yourself wanting to "extract only email addresses," "verify the ...

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 ...

In programming, a set of symbols used to search for occurrences of text or to search and replace text. The simplest regular expressions are DOS/Windows wildcards; for example, *.html refers to all ...

Imagine you are looking for a name in a telephone directory, but you can't remember its exact spelling. You can spend ages searching through all the possible combinations, unless you have a tool that ...

How do you find out if a user has entered a valid email address? Do you check for an at-sign, or is it more complicated? For many developers the answer is a regular expression, a little bit of code ...

Once you get the hang of regular expressions, you'll find them invaluable. The trick is to start small - I'll show you how. Quick: If you shout “regular expressions” in a crowd of Linux users, what ...

When working with regular expressions in a shell script the norm is to use grep or sed or some other external command/program. Since version 3 of bash (released in 2004) there is another option: ...