[Zope] array module and pickleing ques

[Aseem Mohanty]

I am actually porting a previously implemented encryption algorithm to 
be used in Zope and need to be able to differentiate between byte arrays 
and word arrays.

I will try your suggestion. Thanks
AM

Charlie Reiman wrote:

>Testing it from the python interpreter, it appears you are correct.
>array.array is not pickleable. As a wild guess, array is probably a C class
>and they just neglected to add that support. Since you don't say why your
>values must be two bytes, I can't offer any real work arounds.
>
>But as a guess, you might be able to work something with array.array's
>to/fromstring stuff, and keep the array.array in a volatile attribute.
>
>>-----Original Message-----
>>From: zope-admin@zope.org [mailto:zope-admin@zope.org]On Behalf Of Aseem
>>Mohanty
>>Sent: Tuesday, July 09, 2002 10:55 PM
>>Cc: zope@zope.org
>>Subject: Re: [Zope] array module and pickleing ques
>>
>>
>>some more info: the error:
>>
>>Error Type: UnpickleableError
>>Error Value: Cannot pickle objects
>>
>>------------------------------------------------------------------------
>>
>>Troubleshooting Suggestions
>>
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>>   * The parameters passed to this resource may be incorrect.
>>   * A resource that this resource relies on may be encountering an error.
>>
>>For more detailed information about the error, please refer to the HTML
>>source for this page.
>>
>>If the error persists please contact the site maintainer. Thank you for
>>your patience.
>>
>>Traceback (innermost last):
>> File F:\KANDIN~1\lib\python\ZPublisher\Publish.py , line 150, in
>>publish_module
>> File F:\KANDIN~1\lib\python\ZPublisher\Publish.py , line 114, in publish
>> File F:\KANDIN~1\lib\python\Zope\__init__.py , line 158, in
>>zpublisher_exception_hook
>> File F:\KANDIN~1\lib\python\ZPublisher\Publish.py , line 102, in publish
>> File F:\KANDIN~1\lib\python\Zope\__init__.py , line 172, in commit
>> File f:\kandinsky\lib\python\Products\TransactionAgents\__init__.py ,
>>line 54, in new_commit
>> File F:\KANDIN~1\lib\python\ZODB\Transaction.py , line 233, in commit
>> File F:\KANDIN~1\lib\python\ZODB\Connection.py , line 345, in commit
>>   (Info: (('Products.RC2.RC2', 'RC2'), '\x00\x00\x00\x00\x00\x00h\xe1',
>>''))
>>UnpickleableError: (see above)
>>
>>
>>I also tried the following in the python console:
>>
>>Python 2.1.2 (#31, Jan 15 2002, 17:28:11) [MSC 32 bit (Intel)] on win32
>>Type "copyright", "credits" or "license" for more information.
>> >>> import pickle, array, os
>> >>> f= open('test','w')
>> >>> x = array.array('H')
>> >>> pickle.dump(x,f)
>>Traceback (most recent call last):
>> File "<stdin>", line 1, in ?
>> File "F:\KANDIN~1\bin\lib\pickle.py" , line 939, in dump
>>   Pickler(file, bin).dump(object)
>> File "F:\KANDIN~1\bin\lib\pickle.py" , line 109, in dump
>>   self.save(object)
>> File "F:\KANDIN~1\bin\lib\pickle.py" , line 171, in save
>>   raise PicklingError, \
>>pickle.PicklingError: can't pickle 'array' object: array('H')
>> >>>
>>
>>The problem is that I NEED that array sizes to be 1 or 2 bytes  and I
>>dont know how to get around this problem without arrays.
>>
>>Any help would be greatly appreciated.
>>
>>TIA
>>AM
>>
>>Aseem Mohanty wrote:
>>
>>>why does a call to array.array() cause an unpickleable error??
>>>
>>>the pickle docs on the python site dont mention anything about arrays,
>>>nor do the array docs mention about pickling.
>>>
>>>i have a feeling that it might be because of the fact that arrays are
>>>dynamic data structures and thus the pickler doesnt really know about
>>>its limits (of course I could be totally and miserably  wrong) i
>>>couldnt find anything in the docs to support my 'feeling' and the
>>>source is kind of above my current level of expertise in python
>>>
>>>any help would be appreciated or i am doomed to a major rewrite....
>>>
>>>the source in my product that causes the error :
>>>
>>>self.K=array.array('H')
>>>self.L=array.array('B')
>>>self.R=array.array('H')
>>>
>>>TIA
>>>AM
>>>
>>--
>>==================================================================
>> Aseem Mohanty
>> Neurobehavioral Systems Inc, 828 San Pablo Ave, Albany, CA 94706
>> (R) 510 7696011 (M) 510 3014871 (O) 510 5279231
>>============================================================
>>======
>> "I saw `cout' being shifted "Hello world" times to the left and
>>  stopped right there!!"                        -- Steve Gonedes
>>==================================================================
>>
>>
>>
>>
>>
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>
>
>

-- 
==================================================================
 Aseem Mohanty							   
 Neurobehavioral Systems Inc, 828 San Pablo Ave, Albany, CA 94706 
 (R) 510 7696011 (M) 510 3014871 (O) 510 5279231		  	
==================================================================								  	
 "I saw `cout' being shifted "Hello world" times to the left and  
  stopped right there!!"                        -- Steve Gonedes  
==================================================================