[Seaside] tree control?

[Pennell, David]

> Wouldn't this approach end up going back to the server for every
> expansion then?  That seems like unneeded round trips.

Sure, but if you have really huge trees, or if you are displaying "live"
data, this may be what you need to do.  You can use different strategies
(load all at one, load on expansion and keep forever, load on expansion
and keep until collapse, etc.).  Using XMLHTTPRequest would make this
very nice.

-david