W3C home > Mailing lists > Public > public-rdf-dawg@w3.org > April to June 2009

Re: Lee's feature proposal

From: Lee Feigenbaum <lee@thefigtrees.net>
Date: Fri, 01 May 2009 10:30:36 -0400
Message-ID: <49FB078C.8090107@thefigtrees.net>
To: Kendall Clark <kendall@clarkparsia.com>
CC: "Seaborne, Andy" <andy.seaborne@hp.com>, SPARQL Working Group <public-rdf-dawg@w3.org>
Kendall Clark wrote:
> On Fri, May 1, 2009 at 9:24 AM, Seaborne, Andy <andy.seaborne@hp.com> wrote:
>>>      * Negation. The survey indicated strong support for providing a
>>> simpler form of asking negative queries than the current OPTIONAL/!bound
>>> construct. I've excluded this from my proposal under the hope that the
>>> design for subqueries may obviate the need for this feature.
>> I am surprised.
>>
>> It comes out well on the WBS.
> 
> Indeed: we ranked it 2nd just behind the OWL issue.
> 
>> It has user exposure via OPTIONAL!BOUND and that experience is that the current way is hard to use.
> 
> Yes, it's one of those "hacks" that, if you don't notice it when you
> google or no one tells you about it, you miss completely (assuming,
> here, users who don't realize it directly).

As I've said repeatedly, I think the OPTIONAL/!bound construct is a 
major, major stumbling block to learning the language. I think it's just 
about the most important thing the WG can do from an educational point 
of view to fix that. (I personally ranked Negation 4th in my survey 
response). All of which is to say, you don't have to convince me of this.

I'm happy to include it in the proposal, acknowledging that Andy is spot 
on that it's a list of features and not implementations. I mainly left 
it out since the number of features I was proposing was beginning to 
scare me vis a vis our timeline.

> (Btw, all of this applies to assignment, too, for our integrity
> constraint use cases.)

Can you give an example / explain? Is this a use case that is satisfied 
by assignment but not by projected expressions + subqueries?

Lee
Received on Friday, 1 May 2009 14:31:25 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:15:38 GMT