[ZODB-Dev] Tracking down a freeze (deadlock?)

[Jeremy Hylton]

On Fri, 4 Mar 2005 14:45:59 -0500, Tim Peters <tim at zope.com> wrote:
> [Dieter Maurer]
> > "__del__" is a standard Python feature.
> 
> Yes, although its use is discouraged in reality (independent of Zope).

I'd have to say that the vast majority of __del__ methods are read are
unnecessary and prone to failure.  It's a necessary feature, but it's
hard not to wonder if it has been a net loss for Python users through
mis-use.
 
> > The ZODB documentation promisses minimal requirements to make Python
> > classes persistent. It does *NOT* list that "__del__" must not be used.
> 
> I'm not sure which docs you have in mind, but I'm sure that indeed none of
> them say this.  If we decide to disallow __del__, I'm equally unsure of
> where to document it so that people would see it.

Is there a rules of persistence section to Andrew's guide?  Does
anyone read that?  One of ZODB's main goals is to minimize the work
needed to change a regular Python class into a persistent class, but
that's a goal not a contract.

Jeremy