[ZODB-Dev] FW: standalone windows 1.0rc1 exe

[Shane Hathaway]

akuchlin@mems-exchange.org wrote:

> On Wed, Jan 30, 2002 at 12:57:23AM -0500, Barry A. Warsaw wrote:
> 
>>or not, but I think it's convenient.  We're not going to add it for
>>1.0 but as we continue to merge Andrew's distro with ZC's we'll decide
>>one way or the other.
> 
> Let me urge you to add a PersistentList implementation (not
> necessarily my own, in case you have licensing or code quality
> concerns).  In our application, before PersistentList was added, we
> often had bugs where a method mutates a list with .append() and
> doesn't set ._p_changed.  These bugs invariably took a while to track
> down, and using PersistentList made them all go away.  Zope only uses
> the ZODB for storing Web-related documents, an application where
> PersistentMapping is really all you need, but that's a blind spot
> introduced by its Web-focused application domain.

Well, in fact, this issue abounds in Zope as well.  We just have a habit 
of using tuples instead of lists, which is a little dirty, but it works 
out. :-)

The one issue I see with PersistentList is that it puts the list in its 
own database record.  Lists are often small, so having a whole database 
record for every list can be a burden.  There isn't an easy way around 
that in the current ZODB.

... unless the list held a weak reference to its parent... or simply 
knew its parent's OID... hmm...

Shane