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Re: Re: mapping from Turtle grammar to RDF graph

From: Eric Prud'hommeaux <eric@w3.org>
Date: Wed, 3 Feb 2010 07:36:15 -0500
To: Andy Seaborne <andy.seaborne@talis.com>
Cc: Dave Beckett <dave@dajobe.org>, pfps@research.bell-labs.com, semantic-web@w3.org
Message-ID: <20100203123613.GA32619@w3.org>
* Andy Seaborne <andy.seaborne@talis.com> [2010-02-03 09:12+0000]
> 
> 
> On 02/02/2010 9:50 PM, Eric Prud'hommeaux wrote:
> >* Dave Beckett<dave@dajobe.org>  [2010-02-02 07:54-0800]
> >>Eric Prud'hommeaux wrote:
> >>>Peter, all, anyone interested in debugging a mapping from a turtle
> >>>grammar to triple production rules?
> >>>   http://www.w3.org/2010/01/31-Turtle#⋈
> >>>
> >>>I still need to stick encoding issues in there (like \"),
> >>>but this should serve as a start.
> >>
> >>I'm interested and it seems the right direction but I'm finding this a
> >>little hard to understand.
> >
> >I'm certainly sympathetic to that. Any ideas gratefully investigated.
> >
> >>                              I'd hope that we can get out a strong
> >>mapping (like this) which is sufficiently formal that it addresses the
> >>concerns Peter raised in 2008 [1]
> >
> >yeah, that's what motivated this. pfps outlines a recipe and i need to
> >test my recipe against his. his target is ntriples, while i prefer to
> >map to RDF terms and count on the ntriples spec to turn escaped URIs
> >into IRIs.
> >
> >>It also might be worth starting to consider whether to align the terminals
> >>(qnames) more with sparql first.
> 
> That would be good - SPARQL started off with prefixed names defined
> as for XML qnames but feedback was that it did not serve all
> communities very well.  When existing, off web, data has identifier
> systems that have numeric components, the lack of leading digits in
> the local part of prefixed names is a nuisance, so the WG changed
> it.

I was sure that that had influenced the turtle grammar, but
  http://www.w3.org/TeamSubmission/turtle/#nameStartChar
(note no [0-9]) proved you right. The PN_LOCAL I've been using
[56] <PN_LOCAL> ::= ( PN_CHARS_U | [0-9] ) (( (( PN_CHARS | "." ))* PN_CHARS ))?
is identical to SPARQL, so the grammar I propose is more liberal
than the current spec.

> 	Andy

-- 
-ericP
Received on Wednesday, 3 February 2010 12:36:56 GMT

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