Guido van Rossum <guido@python.org> writes:
Is it worth it?
If you believe that the problem is real, yes.
Have you made a patch?
Not yet, no. With Mark's objection, it is more difficult than I thought.
What use case are you thinking of?
People repeatedly complain that pickle consumes too much memory. The most recent instance was http://groups.google.de/groups?selm=slrnal05v1.c05.Andreas.Leitgeb%40pc7499.gud.siemens.at&output=gplain Earlier reports are http://groups.google.de/groups?hl=de&lr=&ie=UTF-8&selm=mailman.1026940226.16076.python-list%40python.org http://groups.google.de/groups?q=pickle+memory+group:comp.lang.python.*&hl=de&lr=&ie=UTF-8&selm=396B069A.9EBDD68B%40muc.das-werk.de&rnum=4
Sorry, what's an identity dict?
IdentityDictionary is the name of a Smalltalk class that uses identity instead of equality when comparing keys: http://minnow.cc.gatech.edu/squeak/1845 In Python, it would allow arbitrary objects as keys, and allow equal duplicates as different keys. For pickle, this would mean that we could save both the creation of the id() object (since the object itself is used as a key), and the creation of the tuple (since the value is only the position). Regards, Martin