[Zope] Empty List Object

[Jim Fulton]

wombat_harness@hotmail.com wrote:
> 
> hi all,
> 
> does anyone know how to check if a list object is empty. Using the
> following code i am getting an error, any thoughts:
> 
> [FORM SIDE OF CODE]
> 
> <TD><INPUT TYPE="checkbox" NAME="delete:list" VALUE="<!--#var
> product_id-->"></TD>
> 
> [FORM PROCESSING SIDE]
> 
>   <!--#in delete-->
>     <!--#var sequence-item-->
>   <!--#else-->
>     Sorry, no deletions
>   <!--#/in-->
> 
> So, what am i doing wrong?

An unfortunate feature of HTML checkboxes is that
unchecked checkboxes aren't included in the form, so
in your case, you don't have an empty list. You don't have a list
at all. Fortunately, the if tag can deal with this:

 <!--#if delete-->
   <!--#in delete-->
     <!--#var sequence-item-->
   <!--#/in-->
 <!--#else-->
   Sorry, no deletions
 <!--#/if-->

Jim

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