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Re: RDF-ISSUE-89 (at-prefix): Should Turtle allow SPARQL's PREFIX like @prefix? [RDF Turtle]

From: Sandro Hawke <sandro@w3.org>
Date: Fri, 11 May 2012 09:42:22 -0400
To: Andy Seaborne <andy.seaborne@epimorphics.com>
Cc: public-rdf-wg@w3.org
Message-ID: <1336743742.3256.6.camel@waldron>
On Fri, 2012-05-11 at 12:14 +0100, Andy Seaborne wrote:
> 
> On 11/05/12 11:48, Steve Harris wrote:
> > On 2012-05-10, at 22:59, Sandro Hawke wrote:
> >
> >> On Thu, 2012-05-10 at 19:53 +0100, Richard Cyganiak wrote:
> >>> Sandro,
> >>>
> >>> I'm sitting on the fence regarding @prefix, and don't like the barewords idea.
> >>>
> >>>> But when I imagine introducing new people to Turtle, as I expect to be
> >>>> doing for many years once it becomes a Recommendation, I can't think of
> >>>> any way to justify that odd character.
> >>>
> >>> It's not just the initial @, also the trailing period. Turtle has:
> >>>
> >>>    @prefix foaf:<http://xmlns.com/foaf/0.1/>.
> >>>
> >>> SPARQL has:
> >>>
> >>>    PREFIX foaf:<http://xmlns.com/foaf/0.1/>
> >>
> >> Indeed, I forgot about that, and Eric reminded me earlier today.  Yes.
> >>
> >>> The period is actually a bigger problem than the @, IMO.
> >>>
> >>> On the other hand, someone who has to learn a completely new language
> >>
> >> My sense is that people moving between Turtle and SPARQL wont think of
> >> it as a completely new language.   Particularly if they learned SPARQL
> >> first, then Turtle is effectively just a subset of Turtle.   But in
> >> either case, I think it will often seem like one language, where SPARQL
> >> just involves using a bunch of extra features of the language.
> >>
> >>> won't be bothered greatly by one extra character here or there, IMO. It's rare that newbies point out inconsistencies in the grammar of a new language that they learn.
> >>
> >> I suppose that depends a lot on the context.   In a SemWeb context,
> >> they're often learning so much other stuff --- well, things like
> >> httpRange-14 draw a lot more heat than @prefix, it's true.
> >>
> >>> The same argument that you make for @prefix can be made for @base. Do you suggest changing @base too?
> >>
> >> Yes, absolutely.
> >>
> >> I might phrase it now as:
> >>
> >> PROPOSED: Make the @-sign and period optional on 'prefix' and 'base' in
> >> Turtle
> >
> > That is an option - but it may be less confusing to allow exactly either:
> >
> > @prefix foo:<http://foo.example/>  .   [N3 style]
> >     or
> > PREFIX foo:<http://foo.example/>       [SPARQL style]
> >
> > You can't put a . between PREFIXes in SPARQL, and I don't think we should add that as an option, it wouldn't fit with the rest of the language.

I think not allowing the period would confuse Turtle-only folks.

> @base vs BASE
> 
> >
> > I'm kind of ambivalent about this, it's probably a good idea, but I've never heard a complaint about it.
> 
> I am more concerned by:
> [[
> with PREFIX preferred and used in all the examples
> ]]

That's what I heard, so I removed that bit when adding the bit about the
period.

   -- Sandro

> >
> > - Steve
> >
> 
> 	Andy
> 
> 
Received on Friday, 11 May 2012 13:42:32 GMT

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