On Tue, Oct 13, 2015 at 12:30:58PM +0200, Ladislav Lhotka wrote: > > > On 13 Oct 2015, at 12:19, Juergen Schoenwaelder > > <j.schoenwael...@jacobs-university.de> wrote: > > > > On Tue, Oct 13, 2015 at 11:45:30AM +0200, Ladislav Lhotka wrote: > >> David Reid <r...@snmp.com> writes: > >> > >>> section 6.3.1 states: > >>> > >>> If a YANG compiler does not support a particular extension, which > >>> appears in a YANG module as an unknown-statement (see Section 14), > >>> the entire unknown-statement MAY be ignored by the compiler. > >>> > >>> If a YANG parser does not support a particular extension, which > >>> appears in a YANG module as an unknown-statement (see Section 14), > >>> the entire unknown-statement MAY be ignored by the parser. Note > >> > >> Implications of this statement are still not clear to me. Let's say some > >> protocol introduces an extension that is critical for that > >> protocol. Does the above sentence mean that an implementation of that > >> protocol MAY ignore the extension if it happens to use a parser that > >> doesn't support it? > >> > >> Lada > >> > >>> that even in this case the semantics associated with the extension > >>> still apply (as if they were part of a description statement). > >>> > > > > Did you read the following sentence: > > > > [...] Note that > > even in this case the semantics associated with the extension still > > apply (as if they were part of a description statement). > > Well, if the parser ignores the extension statement, then the application has > no way to find out that the extension is present to be able to apply its > semantics. >
Description statements have always to be taken into account. > > I think it answers your question with a 'no'. > > Specifying behaviour of a YANG parser using 2119 keywords YANG parser doesn't > make much sense to me, because it all depends on the purpose of the > application that uses the parser. > I do not get your point. The text says a parser may skip over an extension it does not know how to process and it says the semantics still apply as if they were part of a description statement. What is the problem with this? /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
