Re: [netmod] Comment on draft-clacla-netmod-yang-model-update-02

Joe Clarke <> Wed, 15 November 2017 10:27 UTC

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From: Joe Clarke <>
Organization: Cisco
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Date: Wed, 15 Nov 2017 05:27:20 -0500
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Subject: Re: [netmod] Comment on draft-clacla-netmod-yang-model-update-02
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On 11/15/17 05:06, Ladislav Lhotka wrote:
>> I suppose my gut reaction to Lou's question as to whether a server
>> should support multiple versions was, "no."  A client may have multiple
>> versions loaded to support servers that support different versions.  I
>> may be convinced otherwise, but I feel that this will become untenable
>> over time (even if module names change).
> There are use cases for modules that are imported (i.e. not
> implemented): it could be that a module author wants to use some
> definitions from an old version of an imported module while, at the same
> time, other definitions from a new version.
> The semver-aware "import" statement should be able to deal with this.

I think it could be, but I also think importing from different versions
of the same module feels messy.  How would this work with different
module names today?  Just use different prefixes?  Are there defined use
cases for this in the wild today?