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Re: ISSUE-127 (Empty Lists?): What is the effect of @inlist when no triples are generated? [3rd LC Comments - RDFa 1.1 Core]

From: Niklas Lindström <lindstream@gmail.com>
Date: Thu, 23 Feb 2012 11:32:52 +0100
Message-ID: <CADjV5jdVrUBfnRdEvKxM7uv_6R1hxKCN_EfXEKMJNyjURXn-iA@mail.gmail.com>
To: Ivan Herman <ivan@w3.org>
Cc: RDF Web Applications Working Group <public-rdfa-wg@w3.org>
Hi Ivan,

Yes, that's what's important. :) Neither I have a strong option, I
just saw some arguments in favor of the current situation, to help us
evaluate the alternatives. (Given those I'm also fine with leaving
things as is.)

I can't see any alarming problem or confusion from either case in
practice, given that it's mostly an edge case which there are means of
control for either way.

Best regards,
Niklas


2012/2/23 Ivan Herman <ivan@w3.org>:
> Niklas,
>
> to be honest, I have no idea which one is better, although I raised the issue. And to make my position clear: I am actually fine to leave things as is (following the principle of minimal change:-), ie, to generate an empty list, I just wanted to make it so that the WG knows what it is doing:-)
>
> Ivan
>
>
> On Feb 23, 2012, at 10:58 , Niklas Lindström wrote:
>
>> This is an interesting question. I can think of arguments for both
>> sides of the issue.
>>
>> One perspective is that @inlist "collects" members and then puts them
>> in a list if there were any collected.
>>
>> Another perspective might consider @inlist to create the list
>> immediately. This way, it's also more natural to create an empty list
>> if one intends to, rather than using rdf:nil (which is reasonably too
>> technical for casual use). While this can be seen as a difference to
>> how hanging rels behave, I think the difference really lies in the
>> difference between a concrete list of items, and the (perhaps harder
>> to grasp) case of producing multiple statements with the hanging rel
>> "magic". (We had a similar discussion on the JSON-LD telecon
>> yesterday.)
>>
>> Compare this to RDF/XML:
>>
>>  <owl:Class rdf:about="#c">
>>    <owl:unionOf rdf:parseType="Collection"/>
>>  </owl:Class>
>>
>> which produces:
>>
>>  <#c> owl:unionOf () .
>>
>> If one does not want an empty list, one should either leave out the
>> @inlist, or better leave out the entire "list wrapper". This is just
>> like how one have to use a condition for an <ul> depending on whether
>> there will be any <li>:s (since <ul> is not allowed to be empty in
>> HTML). Like in this pseudo-code template:
>>
>>  {% if items %}
>>    <ul rel="owl:unionOf" inlist>
>>      {% for item in items %}
>>        <li resource="{{ item.iri }}">{{ item.label }}</li>
>>      {% endfor %}
>>    </ul>
>>  {% endif %}
>>
>> Does anyone have more concrete usage examples we can consider, to
>> determine which way would be most confusing for authors?
>>
>> Best regards,
>> Niklas
>>
>>
>> On Thu, Feb 9, 2012 at 11:26 AM, RDF Web Applications Working Group
>> Issue Tracker <sysbot+tracker@w3.org> wrote:
>>> ISSUE-127 (Empty Lists?): What is the effect of @inlist when no triples are generated? [3rd LC Comments - RDFa 1.1 Core]
>>>
>>> http://www.w3.org/2010/02/rdfa/track/issues/127
>>>
>>> Raised by: Ivan Herman
>>> On product: 3rd LC Comments - RDFa 1.1 Core
>>>
>>> See http://www.w3.org/mid/CA894838-BFE8-48CC-984D-F304A6D32251@w3.org for further details, this is just to add this question to the issue list.
>>>
>>>
>>>
>>
>
>
> ----
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> FOAF: http://www.ivan-herman.net/foaf.rdf
>
>
>
>
>
Received on Thursday, 23 February 2012 10:33:53 UTC

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