On Mon, Aug 16, 2010 at 12:14 PM, Pedro Ferreira
jose.pedro.ferre...@cern.ch wrote:
Could this be some problem with using persistent objects as keys in a BTree?
Some comparison problem?
I'm not entirely sure about this, but I think using persistent objects
as keys isn't supported. Looking at
PyObject_Compare to compare different keys. Persistent doesn't
implement any special compare function and falls back to the standard
hash algorithm for an object. This happens to be its memory address.
The memory address obviously changes over time and the same address
gets reused for different
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Hanno Schlichting wrote:
On Mon, Aug 16, 2010 at 12:14 PM, Pedro Ferreira
jose.pedro.ferre...@cern.ch wrote:
Could this be some problem with using persistent objects as keys in a BTree?
Some comparison problem?
I'm not entirely sure about this,
On Mon, Aug 16, 2010 at 2:04 PM, Pedro Ferreira
jose.pedro.ferre...@cern.ch wrote:
I think implementing a stable hash function for your type could make
this work though.
From what I read, ZODB doesn't use hash functions, relying on __cmp__
instead. So, I guess I should make my class
On 16 August 2010 13:13, Tres Seaver tsea...@palladion.com wrote:
Hanno Schlichting wrote:
On Mon, Aug 16, 2010 at 12:14 PM, Pedro Ferreira
jose.pedro.ferre...@cern.ch wrote:
Could this be some problem with using persistent objects as keys in a BTree?
Some comparison problem?
I'm not
Consider using one
of these alternatives instead:
* Set the IOTreeSet as an attribute directly on the persistent object.
You mean on the persistent object I am using as key?
* Use http://pypi.python.org/pypi/zope.intid and use the intid for the
key. (This uses
libraries that I'm currently including: location, component, security...
libraries that I'm currently *NOT* including of course :)
--
José Pedro Ferreira
Indico Team
IT-UDS-AVC
513-R-0042
CERN, Geneva, Switzerland
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On 16 August 2010 17:29, Pedro Ferreira jose.pedro.ferre...@cern.ch wrote:
Consider using one
of these alternatives instead:
* Set the IOTreeSet as an attribute directly on the persistent object.
You mean on the persistent object I am using as key?
Yes.
* Use
