If you’re into language parsing and how its patterns could be used in a modern programming language you should take look on Raku (fka Perl 6): It has native support for „Grammars“ [1] which are basically specialized classes to put Regexes in for defining tokens and also combinations of such tokens. Once you‘re done you can use a grammar object to parse text returning an AST object. Raku‘s own syntax is defined in Grammars being a subset of Raku‘s syntax.

So in a nutshell Raku‘s „Grammar“ construct is like RegExes on steroids and renders defining DSLs or other special purpose languages so much easier than in any other modern language.

[1] https://docs.raku.org/language/grammars