Re: [Netconf] [yang-doctors] YANG Doctor question: empty mandatory choice?

Kent Watsen <kwatsen@juniper.net> Thu, 02 August 2018 01:34 UTC

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From: Kent Watsen <kwatsen@juniper.net>
To: Andy Bierman <andy@yumaworks.com>, Robert Wilton <rwilton@cisco.com>
CC: "yang-doctors@ietf.org" <yang-doctors@ietf.org>, "Eric Voit (evoit)" <evoit@cisco.com>, "netconf@ietf.org" <netconf@ietf.org>
Thread-Topic: [yang-doctors] YANG Doctor question: empty mandatory choice?
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Date: Thu, 2 Aug 2018 01:34:47 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/netconf/4AZM2O4bheq3BXmKIwj791GLhm4>
Subject: Re: [Netconf] [yang-doctors] YANG Doctor question: empty mandatory choice?
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> It just seems strange that the model designers are positive the solution belongs in a
> case-stmt inside this choice.  So positive that MUST is in order, which means harm
> to the Internet will happen if this choice is not provided, with no possibility of any
>  exception ever.

Disagree.  As Robert pointed out, the yang update rules allow mandatory true to
become mandatory false.  In my view, choosing to do the "mandatory true" now
is the conservative choice.

PS: I do not believe it is possible to have a receiver that does not define a transport.
       If that were allowed, then it would be vendor magic.

Kent // contributor