RegularExpressionsarenoworsetoreadormaintainthananyotherunformattedcontent;indeedaregexisprobablyeasiertoreadthatthispiecehere-butunfortunatelytheyhaveabadreputationbecausesomeimplementationsdon'tallowformattingandpeopleingeneraldon'tknowthatyoucandoit.

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Here's a trivial example:

 ^(?:[^,]*+,){21}[^,]*+$

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Which isn't really that difficult to read or maintain when it looks like this:

 (?x) # enables comments, so this whole block can be used in a regex.
 ^ # start of string

 (?: # start non-capturing group
 [^,]*+ # as many non-commas as possible, but none required
 , # a comma
 ) # end non-capturing group
 {21} # 21 of previous entity (i.e. the group)

 [^,]*+ # as many non-commas as possible, but none required

 $ # end of string


That's a bit of an over-the-top example (commenting `$` is akin to commenting `i++`) but clearly there should be no problem reading and understanding that, and if maintenance is required it should be fine too.