[Cbor] Regular expression flavors

Carsten Bormann <cabo@tzi.org> Fri, 14 June 2019 11:07 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 14 Jun 2019 13:07:18 +0200
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Subject: [Cbor] Regular expression flavors
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Over in the YANG working group (which calls itself “netmod”), there is an interesting discussion about regex flavors and how W3C XSD regexes are unloved by implementers and prompt open rebellion.

https://mailarchive.ietf.org/arch/browse/netmod/?gbt=1&index=WmiVRg1pEEI_DNupsXnMFCWcwaU

I think this discussion is also relevant for CDDL, even though we already have defined our escape hatch [1].

[1]: https://tools.ietf.org/html/rfc8610#section-3.8.3.2

Still, since W3C XSD Appendix F [2] is our default (and currently only defined) regex flavor, we are likely to run into similar problems with unruly open source communities, so we’d better watch carefully what this does to YANG.  Maybe we also can mount some common efforts, as is being discussed in the referenced thread.

[2]: https://www.w3.org/TR/xmlschema-2/#regexs

Grüße, Carsten