This is a newbie hack at the Q: Maybe you can instantiate foo to a null variable in the REQUEST namespace <dtml-call expr="REQUEST.set(foo,'')"> and then...later in your objects <dtml-unless expr="foo == ''"> <br>yep </dtml-unless> -Trevor
-----Original Message----- From: zope-admin@zope.org [mailto:zope-admin@zope.org]On Behalf Of Kirk Strauser Sent: Tuesday, October 16, 2001 10:04 AM To: zope@zope.org Subject: [Zope] Newbie dereferencing problem
I apologize for the (probably FAQ) newbie problem. FedEx hasn't delivered my copy of "The Zope Book" or "Programming Python" yet, so please forgive me.
Suppose I have the name of an object in variable `foo'. I would like to test for the existence of the named object. Suppose that foo=='bar'. The following won't work:
<dtml-if foo> <br>Yep! </dtml-if>
because `foo' will always have a value. How, then, can I see if `bar' exists?
A million thanks, -- Kirk Strauser
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