This has an almost uncanny-valley effect, in that yes, this is an improved syntax for regular expression, but that has the effect of highlighting why PEGs are t

This has an almost uncanny-valley effect, in that yes, this is an improved syntax for regular expression, but that has the effect of highlighting why PEGs are the way forward here. It's great that you can assign variables in Rulex, but they can't reference themselves recursively, so you're still locked out of all the interesting formats. Meanwhile it weakens the "ok but everyone knows how to use regex, it's in the language, and we're just doing a bit of data munging" argument for choosing regex, and you know what? That's a good argument, and it might be the only one.