W3C home > Mailing lists > Public > www-forms@w3.org > July 2006

Re: Nested <bind>s

From: Erik Bruchez <ebruchez@orbeon.com>
Date: Mon, 24 Jul 2006 16:02:43 +0200
Message-ID: <44C4D303.4@orbeon.com>
To: www-forms@w3.org

Aaron Reed wrote:
> 
> Alessandro Triglia wrote:
>> Hi
>>
>> I have another question.  What is the purpose and significance of 
>> <bind> elements nested within another <bind> element?
>>
>> The schema allows nested <bind>s.  However, the normative text does 
>> not specify what they mean, and there are no examples showing such 
>> nested <bind>s.
>>
>> Alessandro Triglia
>>
> 
> Nested binds have been a point of debate for a while.  You can probably 
> find some of the debate on this very list.  I think that the official 
> stance for XForms 1.0 is that it isn't necessary to support this to be 
> 1.0 compliant since it hasn't been fully hashed out, yet.  I believe 
> that some processors do support nested binds by allowing an inner bind 
> to be relevant to the bind element that contains it.
> 
> I thought that this was going to be addressed in 1.1, but I don't see it 
> there, yet.  Maybe someone from the WG can clarify the status of this 
> issue.  But in short, don't count on any form that you author with 
> nested binds to work across the 1.0 processors.

Mmmh, that's probably one of those things in XForms 1.0 that only appear 
in the schema, I guess (like the nesting of xforms:output within 
xforms:label, and interleaving of xforms:choices, xforms:item, and 
xforms:itemset).

Yet the schema is normative, which means that supporting nested binds is 
actually required by 1.0 implementations.

I was not aware there was a real debate. The only possible issue I think 
was related to what an implementation should do when the parent bind 
returns a nodeset with more than one element, and I think (but somebody 
please correct me if I am wrong) that this translates, like in the case 
of xforms:repeat and xforms:itemset, into applying the children bind 
elements for each node of the outer bind. At least, that's how this is 
implemented in Orbeon PresentationServer, and it seems to make perfect 
sense.

-Erik

-- 
Orbeon - XForms Everywhere:
http://www.orbeon.com/blog/
Received on Monday, 24 July 2006 14:02:46 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 10 March 2012 06:22:05 GMT