[Zope] Calling a DTML method in a subfolder that uses PARENTS[0]

[Soren Roug]

Hello,

I'm trying to call a method inside a folder that uses this common way of
listing its content:

<dtml-in "PARENTS[0].objectValues('File')">
<dtml-var absolute_url><br>
</dtml-in>

Let's call this folder FileLibrary. (It's actually a Z Class subclassed
from ObjectManager)

My problem is when I call the method from the folder above, then PARENTS
is unchanged and the script will try to enumerate the files in the
folder I'm calling from. I've tried several things, e.g.

<dtml-with FileLibrary>...
<dtml-with "_.getitem('FileLibrary')">...

<dtml-with FileLibrary>
<dtml-call "REQUEST.PARENTS.append(_)">...

Nothing works.

How do I get it to work?