"If there are no items in the sequence variable or expression, the optional
else block is executed."
http://zope.org/Documentation/Books/ZopeBook/2_6Edition/AppendixA.stx#2-17
<dtml-in SequenceVariable|expr="SequenceExpression">
[<dtml-else>]
</dtml-in>


Beispiel:
<dtml-in "qx.user.sql_getHighScore(iduser='')" size=10>
   <dtml-var sequence-number>
   <dtml-var player>
   <dtml-var total>
 <dtml-else>
   No games - no ranks.
</dtml-in>