Awk, sed, Perl, editors like VIM and emacs, and many other programs can use regular expressions for pattern matching. Like I said, simple, but powerful and one of the most used command line tools which is why I use it as the example in this article.īut grep isn’t the only program that uses regular expressions. By default, it prints any lines that match the regexp. This is a simple program that takes a regexp and one or more file names (unless you want to read from standard input). Perhaps the most obvious program that uses regular expressions - or regexps, for short - is grep. Let’s look at the foundation you need to understand regular expression well.

The source of confusion is that the details beyond core syntax have variations. Many tools use regular expressions and the core syntax is the same.

They aren’t that hard to learn and there are some great tools to help you. If you aren’t comfortable with regular expressions, that’s easy to fix. Many programs use these as a way to specify search patterns, usually in text strings such as files. One of the pervasive skills that often gives people trouble is regular expressions. But there are certain core skills like file manipulation and editing that will serve you no matter what you do. You might not know how to set up a Wayland server or write a kernel module. With Linux or Unix systems, you can make the same observation.

For example, you can probably boil water, crack an egg, and brown meat. But there are certain things you probably do know how to do that form the basis of many recipes. If you consider yourself a good cook, you may or may not know how to make a souffle or baklava.

Notepad++ regular expression find