Re: [netmod] regular expression flavours (again)

Carsten Bormann <cabo@tzi.org> Fri, 14 June 2019 09:56 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 14 Jun 2019 11:56:35 +0200
Cc: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>, Robert Varga <nite@hq.sk>, NETMOD WG <netmod@ietf.org>
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To: "Rob Wilton (rwilton)" <rwilton@cisco.com>
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Subject: Re: [netmod] regular expression flavours (again)
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On Jun 14, 2019, at 11:29, Rob Wilton (rwilton) <rwilton@cisco.com> wrote:
> 
> I'm sure that someone can post an XKCD of why this is a bad idea 😉

Yeah, going ahead and standardizing another regex dialect that is subtly incompatible with everything else is exactly what we need.

We could even make sure that dialect is actually useful in a pattern statement (e.g., by making it self-anchoring).

But wait, somebody has already done that work for us!

W3C did, when they designed their XSD-types…
So we are done already!

Now the main deployability problem with W3C XSD regexes is that they added some functionality that is sorely missing in other dialects, such as character class subtraction, so it is more than an hour of work to write a converter from XSD regexes to you favorite flavor.  Maybe we should encourage some open source software in this space…

Grüße, Carsten