Re: [Qemu-devel] [PATCH 1/2] qapi: allow flat unions with empty branches

[Markus Armbruster]

Eric Blake <address@hidden> writes:

> On 05/17/2018 03:05 AM, Markus Armbruster wrote:
>>>>>>>> QAPI language design alternatives:
>>>>>>>>
>>>>>>>> 1. Having unions cover all discriminator values explicitly is useful.
>>>>>
>>>>>>>> 2. Having unions repeat all the discriminator values explicitly is not
>>>>>>>> useful.  All we need is replacing the code enforcing that by code
>>>>>>>> defaulting missing ones to the empty type.
>>>>>>>>
>
>>> I think I'd vote for 2 (never enforce all-branches coverage) as well.
>>
>> Eric, what do you think?
>
> I'm sold. Let's go ahead and make the change that for any flat union,
> a branch not listed defaults to the empty type (no added fields)
> rather than being an error, then simplify a couple of the existing
> flat unions that benefit from that.

Anton, would you like to give this a try?

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