Re: [netmod] [Anima] mcr's YANG question raised during the ANIMA WG session

[Michael Richardson <[e-mail]>]

Thank you for very much for the reply.

Jan Lindblad <[e-mail]> wrote:
    > I had a look at your test example. The example is invalid, but pyang
    > fails to detect the error and overwrites some internal structures, with
    > the result below. The root cause of the problem is this:

...

    > Each one of the two uses statement brings in a "container voucher"
    > (with partly different content) at this point in the schema. That is an
    > attempt at a duplicate definition of voucher, which is an error.

okay, so it partly works, which is an error, and I'll see if I can make that
into a test case for pyang.

BUT:
   The goal is exactly to be able to combine two extensions to RFC8366 into a
   new module that has both extensions.  Is there another way to do this?

Puting them into two containers does not accomplish the goal, because now you
have two expires-on, ...

    > Pyang
    > misses this, and overwrites one voucher object with the next, losing
    > some of the content.

    > By placing the two uses statements into separate containers, pyang is
    > able to successfully make a tree:

...

    > Normally in YANG, it wouldn't be hard to to let modules "B" and "C"
    > augment module "A" independently. But here you are working with
    > groupings in such a way that both "B" and "C" build up a complete
    > grouping with everything in "A". When "D" tries to use both "B" and
    > "C", there is inevitably unwanted duplication.

    > If instead, "B" and "C"
    > just defined their little contributions, "D" could import groupings
    > from "A", "B" and "C" and compose them as desired.

The reason I am asking this question now, and proposing this example now, is
so that if there is a better way to build "B" and "C" then we need to know
about that *now*

I see that you have proposed a different way, which I will attempt to work
through.  Fortunately, we still have time to fix some things.