IETF Logo Mail Archive

Re: [netmod] regular expression flavours (again)

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

Return-Path: <cabo@tzi.org>
X-Original-To: netmod@ietfa.amsl.com
Delivered-To: netmod@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 13D0A1200A3 for <netmod@ietfa.amsl.com>; Fri, 14 Jun 2019 02:56:40 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.197
X-Spam-Level:
X-Spam-Status: No, score=-4.197 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_NONE=0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OhZYWKGDCNJ1 for <netmod@ietfa.amsl.com>; Fri, 14 Jun 2019 02:56:38 -0700 (PDT)
Received: from smtp.uni-bremen.de (gabriel-vm-2.zfn.uni-bremen.de [134.102.50.17]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 5072A1200B5 for <netmod@ietf.org>; Fri, 14 Jun 2019 02:56:38 -0700 (PDT)
Received: from [192.168.217.113] (p54A6CA4C.dip0.t-ipconnect.de [84.166.202.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.uni-bremen.de (Postfix) with ESMTPSA id 45QGGX37tKzyvV; Fri, 14 Jun 2019 11:56:36 +0200 (CEST)
Content-Type: text/plain; charset="utf-8"
Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\))
From: Carsten Bormann <cabo@tzi.org>
In-Reply-To: <BYAPR11MB26311142F2841456A42623CDB5EE0@BYAPR11MB2631.namprd11.prod.outlook.com>
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>
X-Mao-Original-Outgoing-Id: 582198993.186554-d220cfd4e541012e660ccc1da02e6566
Content-Transfer-Encoding: quoted-printable
Message-Id: <815A80B5-A05F-4867-BFF4-7C08081F433A@tzi.org>
References: <291106e34498ebd68f26bf9ff9b679dd5bd8f0cd.camel@nic.cz> <20190612092555.xotrr4moh36xv4kl@anna.jacobs.jacobs-university.de> <4611382f-be58-a20f-1712-e5fb3e4ef3ec@hq.sk> <20190613140655.jyq3iltl2v22ekmb@anna.jacobs.jacobs-university.de> <BYAPR11MB26311142F2841456A42623CDB5EE0@BYAPR11MB2631.namprd11.prod.outlook.com>
To: "Rob Wilton (rwilton)" <rwilton@cisco.com>
X-Mailer: Apple Mail (2.3445.9.1)
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/wDMiPmsIS1sNe-87eB8Hfq8CZTE>
Subject: Re: [netmod] regular expression flavours (again)
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: NETMOD WG list <netmod.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netmod>, <mailto:netmod-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/netmod/>
List-Post: <mailto:netmod@ietf.org>
List-Help: <mailto:netmod-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netmod>, <mailto:netmod-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 14 Jun 2019 09:56:40 -0000

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

v2.23.0 | Report a Bug | By Email