BUG?: Saving empty array in shelve

[iwl]

Hi,

I've tryed to save some data containing empty arrays (array('f')) in a
shelve.
It looks like the shelve has some problems with empty arrays, get
allways:
TypeError: ("'NoneType' object is not iterable", <type 'array.array'>,
('f', None))-
Messages when dealing with the readed back shelve.
Seems like I have to avoid empty arrays in a shelve.

[Peter Otten]

iwl wrote:

I've tryed to save some data containing empty arrays (array('f')) in a
shelve.
It looks like the shelve has some problems with empty arrays, get
allways:
TypeError: ("'NoneType' object is not iterable", <type 'array.array'>,
('f', None))-
Messages when dealing with the readed back shelve.
Seems like I have to avoid empty arrays in a shelve.

That seems to be a bug in the underlying pickling mechanism:

>>from array import array
from cPickle import loads, dumps
loads(dumps(array("f", [1])))

array('f', [1.0])

>>loads(dumps(array("f")))

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: ("'NoneType' object is not iterable", <type 'array.array'>, ('f',
None))

Please submit a bug report.

Peter