Pickling Objects inherited from dict (Bug?)

[Thomas Guettler]

Hi!

After unpickling the objects are not the same
any more. Is this a bug or feature?

import pickle

class MyDictContainer (dict):
def __init__(self):
dict.__init__(s elf)
print "MyDictContaine r.__init__"

class MyDict(dict):
def __init__(self, root, name):
dict.__init__(s elf)
self.root=root
self.name=name

container=MyDic tContainer()
for name in ["one", "two", "three"]:
mydict=MyDict(c ontainer, name)
container[name]=mydict

print container
file="data.pick le"
fd=open(file, "w")
pickle.dump(con tainer, fd)
fd.close()

fd=open(file)
unpickle=pickle .load(fd)
fd.close()
print unpickle
Output:

===> python test-pickle.py
MyDictContainer .__init__
{'three': {}, 'two': {}, 'one': {}}
{'one': {},
'three': (<class '__main__.MyDic tContainer'>,
<type 'dict'>, {'three': {},
'two': (<class '__main__.MyDic tContainer'>, <type 'dict'>,
{'three': {}, 'two': {}, 'one': {}}), 'one': {}}), 'two':
(<class '__main__.MyDic tContainer'>, <type 'dict'>,
{'three': {}, 'two': {}, 'one': {}})}

After unpickling the object is not the same anymore.
Any hints?

If I inherit from UserDict instead, the is no error.

thomas

[Michael Hudson]

"Thomas Guettler" <gu*****@thom as-guettler.de> writes:

Hi!

After unpickling the objects are not the same
any more. Is this a bug or feature?

There's a bug report up on SF that may be relavent, try searching
(unfortunately I don't remember the details...).

Cheers,
mwh

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