2010/8/4 Kristján Valur Jónsson :
..
> Well, it is not _that_ dangerous. It just causes cache misses when they
> wouldn't be expected.
> But since this has been brought up and dismissed in issue 8738, I won't
> pursue this further.
Don't read too much from the "dismissal" of issue 8738. I will
> -Original Message-
> From: "Martin v. Löwis" [mailto:mar...@v.loewis.de]
> Sent: 3. ágúst 2010 20:48
> To: Kristján Valur Jónsson
> Cc: Python-Dev
> Subject: Re: [Python-Dev] pickle output not unique
>
> > I just wanted to point this out. W
2010/8/3 "Martin v. Löwis" :
..
> I think there are many other instances where values that compare equal
> pickle differently in Python.
Indeed. For example:
>>> 1.0 == 1
True
>>> dumps(1.0) == dumps(1)
False
or for objects of the same type
>>> 0.0 == -0.0
True
>>> dumps(0.0) == dumps(-0.0)
Fa
2010/8/3 Kristján Valur Jónsson :
..
>
> These strings are different, presumably because of the (ob_refcnt == 1)
> optimization used during object pickling.
>
I have recently closed a similar issue because it is not a bug and the
problem is not present in 3.x: http://bugs.python.org/issue8738
..
>
> I just wanted to point this out. We‘ll attempt some local workarounds
> here, but it should otherwise be simple to modify pickling to optionally
> turn off this optimization and always generate the same output
> irrespective of the internal reference counts of the objects.
I think there are man
Hi there.
I was made aware of this oddity here:
import cPickle
reffed = "xKITTENSx"[1:-1]
print repr(cPickle.dumps(reffed))
print repr(cPickle.dumps("xKITTENSx"[1:-1]))
These strings are different, presumably because of the (ob_refcnt == 1)
optimization used during object pickling.
This might c
