[Zope] Testing if a string isn't empty

[Gitte Wange]

Hello,

I am trying to make some dtml code that tests if a string contains text 
(because if the string is empty it must be set to contain 'Clipname').

Right now the code looks like this:
<dtml-if expr="mc_name == ''">
  <dtml-let mc_name="'Clipname'">
   <dtml-call sqlAddClip>
  </dtml-let>
</dtml-if>

How do you do it - because the above doesn't work.

Regards,
-- 
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Gitte Wange Jensen

System Squid Developer
MMManager Aps
+45 29 72 79 72

gitte@mmmanager.org
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