[Zope] help! dtml-if question

[Jim Washington]

Hi, Anthony

how about:

<dtml-if "_.len(objectValues(['Blurb'])) > 0">

Your _.has_key() (I think you meant _.hasattr()) statement was looking 
for something named "Blurb", not a thing of type"Blurb", so of course it 
failed.

The objectValues(['atype']) statement returns a list of the things of 
the type,  so checking for a non-zero length of the list will do what 
you need.

-- Jim Washington

Dr. Anthony Monta wrote:

> Hi,
> 
> I've tried to find a solution myself but now am stuck.  I created a 
> little "Blurb" product for a university department website so that 
> faculty members can announce recent publications on the department's 
> homepage.  They create these ZClass instances in their own folders, 
> and a DTML method in the top-level folder grabs and displays them at 
> random.  (I want to avoid using ZCatalog for the time being.)  What 
> the method does is randomly choose a faculty folder, and then randomly 
> choose a Blurb instance within that folder.  Here's the hack I came up 
> with:
> 
> <dtml-with Dept>
>  <dtml-with Fac>
>   <dtml-with Sites>
>    <dtml-with "_.whrandom.choice(objectValues(['Folder']))">
>     <dtml-with "_.whrandom.choice(objectValues(['Blurb']))">
>      <dtml-var index_html>
> 
> (end tags omitted)
> 
> The problem is that this method will produce an Index Error when it 
> comes across a folder that doesn't contain an instance of "Blurb" 
> class.  So I need to make the selection of a folder conditional on 
> Zope's finding a Blurb in that folder.  Here's what I tried after 
> reading up:
> 
> <dtml-with Dept>
>  <dtml-with Fac>
>   <dtml-with Sites>
>    <dtml-with "_.whrandom.choice(objectValues(['Folder']))">
>     <dtml-if "_.has_key('Blurb')">
>      <dtml-with "_.whrandom.choice(objectValues(['Blurb']))">
>       <dtml-var index_html>
>        </dtml-with>
>         <dtml-else>
>          Some default Blurb would appear.
> 
> This method fails.  Can someone help?
>