Re: [netmod] if-feature vs. Identifiers and Their Namespaces

Martin Bjorklund <mbj@tail-f.com> Sun, 05 August 2018 11:32 UTC

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Date: Sun, 05 Aug 2018 13:32:06 +0200 (CEST)
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From: Martin Bjorklund <mbj@tail-f.com>
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Subject: Re: [netmod] if-feature vs. Identifiers and Their Namespaces
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Robert Varga <nite@hq.sk>; wrote:
> Hello,
> 
> I have went through RFC7950, but I cannot find the text which would give
> answer whether:
> 
> feature foo;
> feature bar;
> 
> container baz {
>    if-feature "foo and (not baz)";
> }
> 
> list baz {
>    if-feature "(not foo) and baz";
> }
> 
> is valid YANG or not. The two statements violate Section 6.1.2, but they
> are mutually exlusive when conformance comes into play.

I think you mean 6.2.1.  You are right; these two statements violate
6.2.1 and this is thus not legal.

Consider what this would mean in the model above:

  augement /baz {
    ...
  }

> Does compliance (Section 5.6) have any bearing on namespaces (Section
> 6.1.2)?

Section 5.6 is about server conformance, and the first sentence is:

   Conformance to a model is a measure of how accurately a server
   follows the model.

Namespaces are not related to how accurately a server follows a model.



/martin