[Zope3-dev] Re: a bug in the Zope 3 (and 2) page template engine

Fri Apr 20 07:48:18 EDT 2007

Fred Drake wrote:
> On 4/20/07, kit BLAKE <kitblake at gmail.com> wrote:
>> But those attributes *do* work. If you call that image without the
>> attributes, it won't have a title attribute. If you keep the tag as it
>> is, it will have a title attribute.
> 
> This is some pretty freaky behavior for page templates, I think, but
> was by design.  (I don't remember the driving use-case though; sorry.)
> 
> The problem is that Martijn's replacement doesn't start with an
> element, so the attribute insertion fails.  There should probably be a
> more explanatory error message in this case.

No, I don't think that is the cause of the problem, unless I'm missing 
something. This results in the exact same error:

<html>
<img tal:replace="structure python:'<p>Foo</p>'" tal:attributes="title 
python:'bar'" />
</html>

The error message is not just non-explanatory. The error message is an 
indication of a real bug that's been in Zope 3 page templates since SVN 
history began. :)

> I don't really like this behavior, and wouldn't miss it if it were
> disallowed, but the current expectation is that it work when the
> replacement starts with an element.

No, the current expectation is that it works, whatever the replacement 
is. This currently works in Zope 2.8:

<img tal:replace="structure python:'Foo'" tal:attributes="title 
python:'bar'" />

The result is' foo'.

Regards,

Martijn