Re: [Qemu-devel] [PATCH 01/11] QMP: Introduce specification file

[Avi Kivity <avi@redhat.com>]

On 06/30/2009 09:21 PM, Anthony Liguori wrote:
>> 1. Add QValue, QArray, QDictionary
>>
>> QValue is a polymorphic object that can be a number, a string, an 
>> array, or a dictionary.  It needs a bunch of accessors like 
>> qvalue_to_qarray() to check if a value is an array, and things like 
>> qarray_get() or qdict_put() to manipulate them.  For the simpler data 
>> types, qvalue_to_int64() and qvalue_from_int64() should suffice.
>
>
> And add a return value to the monitor functions.  I think this is a 
> good first step.
>
> Passing a QArray to each monitor function is one way to go.  Another 
> way to go is to use something like libffi to do proper dynamic 
> dispatch.  The later approach has the benefit of requiring less code 
> churn and reusing the static type checking.

If/when we switch to passing dictionaries instead of arrays, this won't 
work.  I also think libffi is a little to exotic for something like the 
monitor.
You could potentially introduce some serious ninja action by doing 
something like:

> value = qvalue_create("[%s, {'f': %s, 'b': %s', 'c': %d}]", ...);

Seriously nifty...

-- 
error compiling committee.c: too many arguments to function