[Zope] How to tree from top?

[Loren Stafford]

As usual, just asking the question helped me find the answer by myself.

This syntax works:

 <!--#tree expr="PARENTS[-1]" -->

> 
> I want to make a tree for navigation that always starts from the topmost
> object regardless of the level of the current object.
> 
> But what is the ID of the topmost object?
> 
> I tried <!--#tree "PARENTS[-1]" -->, but that gets an error.
> 
> I tried enclosing the tree in <!--#with "PARENTS[-1]"--> but that doesn't
> work either.