dgdev <[EMAIL PROTECTED]> wrote:
> I would like to pickle an extension type (written in pyrex). I have
> it working thus far by defining three methods:
>
> class C:
> # for pickling
> __getstate__(self):
> ... # make 'state_obj'
> return state_obj
>
> __reduce__(self):
> return C,(args,to,__init__),me.__getstate__()
>
> # for unpickling
> __setstate__(self,state_obj):
> self.x=state_obj.x
> ...
>
>
> This gets the class pickling and unpickling.
>
> However, I'd like to not specify arguments for __init__ (as I do now
> in __reduce__), and so not have __init__ invoked during unpickling.
>
> I would like to have the pickling machinery somehow create an
> uninitialized object, and then call its __setstate__, where I can re-
> create it from 'state_obj'.
>
> Is there a kosher way to do so, that is without me having to have a
> special mode in the constructor for when the object is being created
> by the unpickler?
I don't understand why you have a problem -- __init__ is NOT called by
default upon loading an object w/__setstate__. Witness:
>>> class C(object):
... def __init__(self, *a): print 'init', a
... def __getstate__(self): print 'gs'; return {}
... def __setstate__(self, *a): print 'ss', a
...
>>> c = C()
init ()
>>> s = cPickle.dumps(c, 2)
gs
>>> s
'\x80\x02c__main__\nC\nq\x01)\x81q\x02}b.'
>>> z = cPickle.loads(s)
ss ({},)
Perhaps you're not using protocol 2? You should be...
Alex
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