[Zope] Unique incrementing IDs

[Kevin Dangoor]

Hi,

    Since Zope is multithreaded, it seems like there could be a problem
doing something like this:

<dtml-comment newid is a folder property>
<dtml-call "REQUEST.set('newid', newid + 1)">
<dtml-call "manage_changeProperties(REQUEST)">
<dtml-call "REQUEST.set('id', newid)">
<dtml-with "manage_addProduct['SomeProduct']">
<dtml-call "ZClass_add(_.None, _)">
</dtml-with>

It seems plausible that you might end up trying to create two objects with
the same ID. This will obviously fail, but it would be nice if there was an
easy way to get the next ID sequentially like this. Am I correct in assuming
that there may be a condition where it tries to create two objects with the
same ID?

Kevin