[IronPython] Portable use of pickle.dumps()

[Michael Foord]

Robert Smallshire wrote:
> Michael,
>
>   
>> Michael Foord wrote:
>>     
>>> [snip...]
>>> Here is an example of getting a byte array from a binary pickle in
>>> IronPython:
>>>
>>>       
>>>>>> import pickle
>>>>>> class A(object):
>>>>>>             
>>> ...  b = 'hello'
>>> ...  c = (None, 'fish', 7.2, 7j)
>>> ...  a = {1: 2}
>>> ...
>>>       
>>>>>> p = pickle.dumps(A(), protocol=2)
>>>>>> p
>>>>>>             
>>> u'\x80\x02c__main__\nA\nq\x00)\x81q\x01}q\x02b.'
>>>       
>>>>>> from System import Array, Byte
>>>>>> a = Array[Byte](tuple(Byte(ord(c)) for c in p))
>>>>>> a
>>>>>>             
>>> Array[Byte]((<System.Byte object at 0x0000000000000033 [128]>,
>>> <System.Byte obje...
>>>
>>>       
>> And the converse:
>>
>>  >>> p2 = ''.join(chr(c) for c in a)
>>  >>> a2 = pickle.loads(p2)
>>  >>> a2
>> <A object at 0x000000000000004E>
>>  >>> a2.a
>> {1: 2}
>>  >>> a2.b
>> 'hello'
>>  >>> a2.c
>> (None, 'fish', 7.2, 7j)
>>     
>
> As a result of applying your str <--> Array[Byte] transformations to my
> code, the persistence of pickles into SQLite BLOBs is now working as
> planned. :-)
>
> You'll also no doubt be pleased to hear that even with these extra
> transformations, the IronPython version is around twice as fast as CPython
> 2.6 on a benchmark performed under completely unscientific conditions -
> although there are many factors at play here...
>
>   

Cool. :-)

Michael

> Thanks again,
>
> Rob
>   


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