Jeff Gentry wrote:
I'm running Zope 2.7.3 w/ python 2.4.1.  I'm in the process of developing
a FS based product as a primary class w/ many sub-classes.  I've been
experiencing a problem which I thought I had completely nixed but
apparently only partly so and now am out of ideas as to what might be the
source of the problem.

As background, the primary class (A) maintains a handle to an instance of
another class (B) which handles interaction w/ a psycopg db
controller.  Class A also will instantiate several instances of Class C
and as part of the construction will pass it the handle to class B.  So in
summary, A has a B and has 1:n C's, and C has a reference to B.  A & B
have physical representations in the ZMI, while instances of C are

We say that A and B are persistent classes, while C is not.
You have to be aware that persistent classes have special needs, and using them has consequences. One being that, due to transactional behaviour, several versions of the same instance of an object may be present in the system, in different threads, for different requests. They'll have different addresses.

Also be aware that it doesn't make sense for a non-persistent class to refer to a persistent instance unless it knows that they can be thread-specific.


Florent Guillaume, Nuxeo (Paris, France)   CTO, Director of R&D
+33 1 40 33 71 59   [EMAIL PROTECTED]
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