[Python-ideas] Json object-level serializer

[M.-A. Lemburg]

Georg Brandl wrote:
> Am 29.07.2010 14:31, schrieb M.-A. Lemburg:
>> Georg Brandl wrote:
>>> Am 29.07.2010 13:35, schrieb Tarek Ziadé:
>>>> Hello,
>>>>
>>>> What about adding in the json package the ability for an object to
>>>> provide a different object to serialize ?
>>>> This would be useful to translate a class into a structure that can be
>>>> passed to json.dumps
>>>>
>>>> So, it __json__ is provided, its used for serialization instead of the
>>>> object itself:
>>>>
>>>>>>> import json
>>>>>>> class MyComplexClass(object):
>>>> ....     def __json__(self):
>>>> ....         return 'json'
>>>> ....
>>>>>>> o = MyComplexClass()
>>>>>>> json.dumps(o)
>>>> '"json"'
>>>
>>> You can do this with a very short subclass of the JSONEncoder:
>>>
>>> class MyJSONEncoder(JSONEncoder):
>>>     def default(self, obj):
>>>         return obj.__json__()  # with a useful failure message
>>
>> Does that also work with the JSON C extension ?
> 
> I think so.  The C encoder gets the default function as an argument.

Then that sounds like the right way forward.

-- 
Marc-Andre Lemburg
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