On Thu, Jul 30, 2015 at 01:31:01PM +0200, Jernej Tuljak wrote: > Ladislav Lhotka je 30.7.2015 ob 11:30 napisal: > >>On 30 Jul 2015, at 01:12, Andy Bierman <a...@yumaworks.com> wrote: > >> > >> > >> > >>On Wed, Jul 29, 2015 at 10:51 AM, Martin Bjorklund <m...@tail-f.com> wrote: > >>Andy Bierman <a...@yumaworks.com> wrote: > >>>Hi, > >>> > >>>I understand the intent is that an implementation of NACM > >>>has to understand these NACM extensions. I agree with Lada > >>>that the YANG text about MAY ignore extensions casts doubt whether > >>>this sort of NACM rule is enforceable or specified correctly. > >>So do you agree that it would be a good idea to clarify this > >>according to Juergen's suggestion? > >> > >> > >> > >>Not really. > >>Pretending the extension is just another description-stmt > >>does not really fix anything. > >In fact, generic tools like pyang ignore what’s written in descriptions. > > Where does RFC6020 say that description-stmt may be used for defining > additional semantics? The only instance where I can find "description" > and "semantics" or "meaning" in the same sentence, is in the section > that describes module updates. This is what a YANG description is: > > The "description" statement takes as an argument a string that > contains a human-readable textual description of this definition. > The text is provided in a language (or languages) chosen by the > module developer; for the sake of interoperability, it is RECOMMENDED > to choose a language that is widely understood among the community of > network administrators who will use the module. > > A textual description for humans. A docstring. I don't see semantics > being mentioned anywhere, so where is all this coming from?
Seriously? Perhaps we have a different understanding of the word 'semantics'. Anyway, description statements (or DESCRIPTION clauses back in SMIv2) have always been used to provide semantics that are not expressable in machine readable form. Example: The ietf-yang-types:counter32 definition defines a counter type because of the text in the description statement. I would say there is lots of semantics in the description statement. Without the description statement, the ietf-yang-types:counter32 would not at all be a counter. I am absolutely surprised lately how little we seem to have a common understanding about basic YANG concepts. /js -- Juergen Schoenwaelder Jacobs University Bremen gGmbH Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany Fax: +49 421 200 3103 <http://www.jacobs-university.de/> _______________________________________________ netmod mailing list netmod@ietf.org https://www.ietf.org/mailman/listinfo/netmod
