Re: [Qemu-devel] [PATCH v2 2/6] qapi: support nested structs in OptsVisitor

[Markus Armbruster]

"Kővágó Zoltán" <address@hidden> writes:

> 2015-06-17 13:18 keltezéssel, Markus Armbruster írta:
>> Copying Kevin because similar issues exist in the block layer.
>>
>> Gerd Hoffmann <address@hidden> writes:
>>
>>> On Mi, 2015-06-17 at 09:50 +0200, Markus Armbruster wrote:
>>>> Copying László because his fingerprints are on OptsVisitor.
>>>>
>>>> "Kővágó, Zoltán" <address@hidden> writes:
>>>>
>>>>> The current OptsVisitor flattens the whole structure, if there are
>>>>> same named
>>>>> fields under different paths (like `in' and `out' in `Audiodev'),
>>>>> the current
>>>>> visitor can't cope with them (for example setting
>>>>> frequency=44100' will set the
>>>>> in's frequency to 44100 and leave out's frequency unspecified).
>>>>>
>>>>> This patch fixes it, by the following changes:
>>>>> 1) Specifying just the field name will apply to all fields that has the
>>>>>     specified name (this means it would set both in's and out's
>>>>> frequency to
>>>>>     44100 in the above example).
>>
>> What if they have different types?
>>
>> What if one of them can't take the value?
>
> Currently it will error out, requiring the user to be more
> explicit. Probably not the best solution, but I can't really think of
> a better solution. (If we would ignore invalid values that would be
> very confusing imho.)

Yes, we clearly don't want foo=0 to set a.foo and b.foo, but foo=x set
only a.foo, because the former can take any string, but the latter only
a number.

Can we require the LHS to be unambiguous?

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