Regex madness

I'm a big fan of regexes, the problems they solve, and the problems they create. It reminds me of Perl :p

Lately I've encountered a couple of very twisted uses of them worth a post.

First of all is a very nasty way of using the regex engine as a sintactic transformer that ends up validating arithmetic operations. Totally nuts.

• http://www.drregex.com/2018/09/a-regex-i-submitted-to-reddit-climbed.html 

Second one is a kind of "sed for power users". It's about internals of sed at a user level (as strange as it seems).

• http://tech.bluesmoon.info/2008/09/programming-patterns-in-sed.html 

After reading drregex post I started hunting for that Abigail's slides on how to solve sudoku using regexes.

• http://perl.abigail.be/Talks/Sudoku/HTML/index.html 

And here is Brian d Foy explaining how to parse json with a single regex.

• https://www.youtube.com/watch?v=-O-Uajd2WzU 

Last one is my metaII bootstrapping parser. A single regex to bootstrap the metacompiler. I guess it also counts as crazyish.

• https://github.com/kidd/meta-II/blob/master/metaII.pl