Regular expressions are patterns that provide a powerful way to search and replace in text. In JavaScript, they are available via the RegExp object, as well as being integrated in methods of strings.

Oniguruma is a regular expression engine written in C that's used in Ruby (via a fork named Onigmo), PHP (mb_ereg, etc.), TextMate grammars (used by VS Code, Shiki, etc. for syntax highlighting), and ...