[Zope] getattr default

Casey Duncan c.duncan@nlada.org
Mon, 29 Oct 2001 09:52:59 -0500

On Monday 29 October 2001 08:26 am, Mitch Model allegedly wrote:
> What's wrong with the 'getattr' call in this DTML method?  I get an
> error message:  "Name not found or not allowed undefined." (using ZDebug).
> (The problem is not the choice of attribute names -- I get it whatever I
> type that isn't an attribute in the REQUEST.)  If I arrange to get into pdb
> from this method, the getattr expression works fine.  Is this a Zope bug?
> _____________________________________________________________________
> <html>
> <body>
> REQUEST does
> <dtml-if expr="not _.hasattr(REQUEST,'undefined')">
> not
> </dtml-if>
> have the attribute 'undefined'.
> <p>
> value = <dtml-var expr="_.getattr(REQUEST, 'undefined', 'nothing')">
> </body>
> </html>
> _____________________________________________________________________

Calling hasattr on REQUEST is not allowed from DTML, and is not necessary. 
Try using has_key instead, as in:

<dtml-if expr="REQUEST.has_key('whatever')">

To get the desired default value behavior, user REQUEST.get:

value = <dtml-var expr="REQUEST.get('somevar', 'nothing')">

  Casey Duncan, Sr. Web Developer
  National Legal Aid and Defender Association