[Zope] Tree tag and SQL methods?

[Ty Sarna]

In article <B059671903C6D211A0D500C0F0301C7910C83D@kubrick.mop.no>,
Alexander Staubo  <alex@mop.no> wrote:
> I'm thinking of exploiting the #tree tag in conjunction with one or more
> SQL method. Say I have a hierarchical-ish table with id/parent_id
> references, and I'd like to display this information in a nice
> collapsible tree. Possible? Possibly the expr= or branches_expr=
> arguments to #tree could evaluate the result of an SQL method, although
> it sounds to me like this would require one query per tree level.

I did something like this with a TinyTable once for fun. I made a brain
that provided a tpValues method which recursively queries for children.
I had to modify TinyTables to use itself as the acquisition parent for
results so it could find itself to use in the recursive queries (it
normally doesn't do this, because that causes unexpected acquisition
inside an #in). I never bothered to find a cleaner way of doing this
since I was just fooling around.

> Possibly you could put the query results of the complete table in a
> temporary variable and evaluate on that?

That'd be a better way. It shouldn't be hard to write an external method
that "treeifys" any Results instance, so you can #tree anything that you
can #in on.