Fixed Re: [ZODB-Dev] Help!

[JohnD.Heintz]

On Thursday 16 August 2001 07:17, Greg Ward wrote:
> On 15 August 2001, John D . Heintz said:
> > For everyone benifit I've included our HashablePersistent code.  Plea=
se
> > let me know if I've messed anything else up, but it seems to be worki=
ng
> > for us.
> >
> > John
> > class HashablePersistent(Persistent):
> >     def __hash__(self):
> >         """
> >         Trivial __hash__ implementation to get identity
> >         """
> >         if not self._p_oid:
> >             someGlobal.ensurePid(self)
> >         result =3D hash(self._p_oid)
> >         return result
>
> What is ensurePid() -- something of your own devising, or is it lurking
> deep in the bowels of ZODB?

It is our own code.  I tried to imply that, but should have said myGlobal=
 or=20
something. =20

It resolves to a per session data structure that behaves like=20
CoreSessionTracking.  The ensurePid() function adds a temp reference to s=
elf=20
and calls a get_transaction().commit(1) to make sure that the object has =
a=20
_p_oid value.

>
> And shouldn't it really be called ensureOID()?

Probably, but I am really only concerned with the general idea of a=20
persistent id, not the details of _p_oid here. =20

>
> >     def __cmp__(self, other):
> >         if self._p_oid is None:
> >             someGlobal.ensurePid(self)
> >
> >         if id(self) =3D=3D id(other):
> >             return 0
>
> Usually spelled "if self is other", but maybe that's me.

Your right, thanks.  We've made the change.

>
>         Greg
>
> _______________________________________________
> For more information about ZODB, see the ZODB Wiki:
> http://www.zope.org/Wikis/ZODB/
>
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--=20
=2E . . . . . . . . . . . . . . . . . . . . . . .

John D. Heintz | Senior Engineer

1016 La Posada Dr. | Suite 240 | Austin TX 78752
T 512.633.1198 | jheintz@isogen.com

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