-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Robert Gravina wrote: > > On 2006/06/27, at 3:49, Benji York wrote: > >> Robert Gravina wrote: >>> I just tried loading a persisted object interactively and noticed >>> that although the _p_oid doesn't print out as anything (and hence I >>> always thought it was empty in my debugging prints), it isn't >>> actually None! Can anyone explain this? (here "p" is my persisted >>> object) >>> >>> p._p_oid >>> '\x00\x00\x00\x00\x00\x00\x00\x08' >>> >>> print p._p_oid >>> >>> p._p_oid is None >>> False >> >> What would you expect to see if you printed out seven null characters >> and a backspace? > > Hahaha - that's a good point! I was expecting IDs to look, well, > something like "asdf23asdf". Well, anyway thankyou! I seemed to have > solved this problem. I was able to write a __eq__ function like this: > > def __eq__(self, other): > if isinstance(other, <name of my class>): > if hasattr(other,"_p_oid") and other._p_oid != None and > (other._p_oid == self._p_oid): > return True > else: > return False > > and now can compare objects for equality after the (Twisted) client > edits them and sends them back. > > Anyway, thanks again.
Note that 'hasattr' swallows *all* exceptions, including some which might not be appropriate. I think I would recommend: if isinstance(other, <my class>): o_jar = getattr(other, '_p_jar', None) o_oid = getattr(other, '_p_oid', None) return ( o_jar and o_oid and o_jar == self._p_jar and o_oid == self._p_oid) since OIDs are guaranteed to be unique only within the scope of a given database (the '_p_jar' is a connection to the database). Tres. - -- =================================================================== Tres Seaver +1 202-558-7113 [EMAIL PROTECTED] Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v220.127.116.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFEoDQU+gerLs4ltQ4RAnrPAKCuR/ZL+btXAzz6tQ/TPhycLbGM5gCglPXB f/O+EhSS2QgfEyikJQi7wqA= =meKl -----END PGP SIGNATURE----- _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev