[Zope] <dtml-tree, the bane of my life :(

[Chris Withers]

Okay, firstly, I notice dtml-tree doesn't support the standard
abbreviation:

<dtml-TAG "x"> -> <dtml-TAG expr="x">

As the following:

<dtml-tree "_.getitem('sequence-item',0)" branches="postingValues">

gives me:

Error Type: KeyError
Error Value: "_.getitem('sequence-item',0)"

nice...

Now the one that has me stumped :(

Why does the following:

<dtml-tree expr="_.getitem('sequence-item',0)" branches="postingValues"> 

Give me:
Error Type: NameError
Error Value: _

This is all in 2.1.6...

cheers,

Chris

PS: The traceback for the last one:
Traceback (innermost last):
  File E:\Zope\2179E4~1.6\lib\python\ZPublisher\Publish.py, line 214, in
publish_module
  File E:\Zope\2179E4~1.6\lib\python\ZPublisher\Publish.py, line 179, in
publish
  File E:\Zope\2179E4~1.6\lib\python\Zope\__init__.py, line 202, in
zpublisher_exception_hook
    (Object: ElementWithAttributes)
  File E:\Zope\2179E4~1.6\lib\python\ZPublisher\Publish.py, line 165, in
publish
  File E:\Zope\2179E4~1.6\lib\python\ZPublisher\mapply.py, line 160, in
mapply
    (Object: manage_postings)
  File E:\Zope\2179E4~1.6\lib\python\ZPublisher\Publish.py, line 102, in
call_object
    (Object: manage_postings)
  File E:\Zope\2179E4~1.6\lib\python\App\special_dtml.py, line 120, in
__call__
    (Object: manage_postings)
    (Info:
E:\Zope\2.1.6\lib\python\Products\Squishdot/Squishdot_manage_postings.dtml)
  File E:\Zope\2179E4~1.6\lib\python\DocumentTemplate\DT_String.py, line
502, in __call__
    (Object: manage_postings)
  File E:\Zope\2179E4~1.6\lib\python\DocumentTemplate\DT_In.py, line
691, in renderwob
    (Object: postingValues)
  File E:\Zope\2179E4~1.6\lib\python\TreeDisplay\TreeTag.py, line 152,
in render
    (Object: a tree tag)
  File E:\Zope\2179E4~1.6\lib\python\DocumentTemplate\VSEval.py, line
208, in eval
    (Object: _.getitem('sequence-item',0))
  File <string>, line 0, in ?
NameError: (see above)