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Date: Mon, 17 May 2010 11:13:53 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH 3/8] Add QBuffer
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Juan Quintela <quintela@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Markus Armbruster <armbru@redhat.com>, Luiz Capitulino <lcapitulino@redhat.com>

On 05/17/2010 11:10 AM, Avi Kivity wrote:
>
> Another way of looking at it: if the client sees { __class__: foo, f1: 
> 10, f2: 9 }, it cannot derive any information from __class__ unless it 
> was aware of foo beforehand.  If that's the case, let's make it part 
> of the schema so it is available at compile time instead of runtime.
>

Or both.  That's similar to a non-object field's type being described 
both in the schema at during runtime.  A static parser can verify 
__class__ matches the expectations, a dynamic parser can look up 
__class__ and call the appropriate constructor.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.