Whenever I write a regex, I end up with a comments roughly ten times longer than the regex. That being said, regular expressions are often the right tool for the job (i.e. parsing a regular language, as opposed to a context-free language or whatever), just the syntax becomes unreadable rather quickly. I’m sure you could build a nicer regular-expression syntax in Haskell.

I love the verbose flag[0] to regex, so I can write comments inline.

[0] https://docs.python.org/3/library/re.html#re.VERBOSE

Yes. Regex tend to become rather fast write only. One solution is commenting, but is still complex. What I like to do now (in C) is define parts of it. Just a crude example to get the idea:

   // STRing: matches anything inside quotes (single or double)
   #define STR "[\"'](.*)[\"']"
   // NUMber: matches decimal or hexadecimal numbers
   #define NUM "([[:digit:]]x?[[:xdigit:]]*)"
   
   regcomp(&reg_exp, STR NUM , REG_EXTENDED | REG_ICASE);

> just the syntax becomes unreadable rather quickly. I’m sure you could build a nicer regular-expression syntax in Haskell.

Of course regular expressions are really more of a category of expressions, and the traditional kleene star notation is only one of many options; regular expressions do not somehow inherently need to use that specific syntax.

Pomsky and VerbalExpressions are just some examples of alternative syntaxes for regex. Apparently there is even a port of VerbalExpressions for Haskell:

https://github.com/VerbalExpressions/HaskellVerbalExpression...