Re: Turtle implementation report for RDF::Trine

Hi Greg,

On Apr 17, 2013, at 09:50, Gregory Williams <greg@evilfunhouse.com> wrote:

> On Apr 17, 2013, at 10:16 PM, David Wood <david@3roundstones.com> wrote:
> 
>> Hi Greg,
>> 
>> Thank you for your comments.  Apologies for not responding earlier.  That was our oversight.  I will also ask the Turtle editors to respond to you.
>> 
>> Alignment with SPARQL syntax was literally the first issue raised for this working group.  Please see the issue and a small portion of the notes and email discussions around it here:
>> http://www.w3.org/2011/rdf-wg/track/issues/1
>> 
>> The working group did resolve to include this alignment and it was marked "at risk" pending comments from the community.  We will see whether others feel as strongly as you do during the remainder of the comment period.
>> 
>> *Personally* (and thus not as co-chair), I think it is much more important to optimize for user time than implementor time.  Although these changes make the grammar much less clean, they also remove the most common cause of invalid Turtle creation by hand and by code.  That is worth something substantial to many people.
> 
> Dave,
> 
> Thanks for the quick response.
> 
> I took a look at the discussion around ISSUE-1, but didn't see anything directly about the @prefix vs. PREFIX syntax difference.


There is a note in ISSUE-1 that shows that the SPARQL 1.1 syntax was "practically frozen" by the time the RDF working group was established (23 Feb 2011, 16:28:05).  Unfortunately for Turtle syntax, we had very little ability to change SPARQL.

There is also a note that the working group resolved that SPARQL and Turtle syntax should be "the same except for well-motivated (and small) exceptions." (resolved at 13 Oct 2011, 17:24:43 UTC)

Both of those notes suggest @prefix and PREFIX syntax alignment.

We resolved to accept the alternative @base and @prefix syntaxes without trailing periods on 16 May 2012.  See the discussion preceding the resolution:
  http://www.w3.org/2011/rdf-wg/meeting/2012-05-16#resolution_2

We resolved (again) on 9 Jan 2013 that the grammar productions for @base and @prefix would be at risk:
  http://www.w3.org/2011/rdf-wg/meeting/2013-01-09#resolution_2

We resolved on 13 Feb 2013 regarding concatenation due to @base and @prefix changes:
  http://www.w3.org/2011/rdf-wg/meeting/2013-02-13#resolution_1

The working group also considered:

- Differences between SPARQL 1.0 and Turtle:
  http://www.w3.org/2011/rdf-wg/wiki/Diff_SPARQL_Turtle

- Placement of prefixes in SPARQL and Turtle:
  See the thread starting at http://lists.w3.org/Archives/Public/public-rdf-wg/2012Jun/0048.html

> 
> I understand you're not an editor, but could you comment on how you think optimizing "for user time" interacts with my concern about having two different rules about trailing dots? My concern is about optimizing for both implementors and users, but since implementations happen once but use of those implementations again and again, I'm actually much more concerned with the potential impact of these grammar rules on users in this case.

I think Eric P. answered this question and I agree with his perspective.

I hope that helps!

Regards,
Dave
--
http://about.me/david_wood


> 
> thanks,
> .greg
>