John schrieb: > Hi there, > > I have a rather lengthy program that troubles me for quite some time. After > some debugging, I arrived at the following assertion error: > > for e in edges.keys(): > assert edges.has_key(e) > > Oops!? Is there ANY way that something like this can possibly happen?
Yes, it happens when another part of your program -- most likely a thread -- modifies edges while you are iterating over its keys. The keys() method of a dict returns a *copy* of its keys. If you had uses "for e in edges" you'd have seen a RuntimeError "dictionary changed size during iteration". With keys() you see the snapshot of edges's keys when keys() is called. Christian PS: Use "e in edges" instead of "edges.has_key(e)". It's faster. -- http://mail.python.org/mailman/listinfo/python-list
