Hi all, I have a module that saves and loads data using cPickle, and
I've encountered a problem. Sometimes I want to import the module and
use it in the interactive Python interpreter, whereas sometimes I want
to run it as a script. But objects that have been pickled by running the
module as a script can't be correctly unpickled by the imported module
and vice-versa, since how they get pickled depends on whether the
module's __name__ is '__main__' or 'mymodule' (say). I've tried to get
around this by adding the following to the module, before any calls to
cPickle.load:
if __name__ == '__main__':
import __main__
def load(f):
p = cPickle.Unpickler(f)
def fg(m, c):
if m == 'mymodule':
return getattr(__main__, c)
else:
m = __import__(m, fromlist = [c])
return getattr(m, c)
p.find_global = fg
return p.load()
else:
def load(f):
p = cPickle.Unpickler(f)
def fg(m, c):
if m == '__main__':
return globals()[c]
else:
m = __import__(m, fromlist = [c])
return getattr(m, c)
p.find_global = fg
return p.load()
cPickle.load = load
del load
It seems to work as far as I can tell, but I'll be grateful if anyone
knows of any circumstances where it would fail, or can suggest something
less hacky. Also, do cPickle.Pickler instances have some attribute
corresponding to find_global that lets one determine how instances get
pickled? I couldn't find anything about this in the docs.
--
Hate music? Then you'll hate this:
http://tinyurl.com/psymix
--
http://mail.python.org/mailman/listinfo/python-list
