Regular expressions (regexp) — the basics
21 min
Translation
Regular expressions (also called regexp, or regex) are a mechanism for finding and replacing text. In a string, a file, multiple files... They are used by developers in application code, testers in autotests, and even just when working on the command line!
Why is this better than a simple search? Because it allows you to specify a pattern.
For example, you receive a date of birth in the DD.MM.YYYYY format. You need to pass it on, but in the YYYY-MM-DD format. How can you do this with a simple search? You don't know in advance what the exact date will be.