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Re: SPARQL grammar... in BNF? N3?

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Wed, 08 Feb 2006 16:08:56 +0000
Message-ID: <43EA1798.8030809@hp.com>
To: Dan Connolly <connolly@w3.org>
CC: "Eric Prud'hommeaux" <eric@w3.org>, Yosi Scharf <syosi@MIT.EDU>, Tim Berners-Lee <timbl@w3.org>, public-cwm-talk@w3.org, Robert Crowell <crowell@MIT.EDU>

A few details:

Dan Connolly wrote:
> Yosi, Tim, Eric,
> 
> The SPARQL parser in cwm... it seems to be built from EricP's
> BNF...
> 
> 
> |    if web:
> |        File = urllib.urlopen('http://www.w3.org/2005/01/yacker/uploads/sparqlTest/bnf')

Now:

http://www.w3.org/2005/01/yacker/uploads/SPARQL/bnf

>  -- http://www.w3.org/2000/10/swap/sparql/sparql-grammar.py
> 
> In the DAWG, the editors added a .jj version of the grammar

I hope we will add all the parsers - adding the .jj is just a start.  We just 
need a place outside yacker (where they can be mutated) and put somewhere that 
can be linked to for publication.

> and are considering what other formats to publish.
>   http://www.w3.org/2001/sw/DataAccess/rq23/parsers/sparql.jj
>   <- http://www.w3.org/2001/sw/DataAccess/rq23/parsers/
>   <- http://www.w3.org/2001/sw/DataAccess/rq23/#sparqlGrammar
> 
> Is BNF the one we want/need?
> 
> EricP, have you generated a turtle/n3 version of the SPARQL grammar?

The grammars in yacker (grammar name = SPARQL) are up to date, including the 
BNF (which is the same as rq23 - because it is extracted from rq23 and then
1/ All \ are escaped.
2/ @terminals added).

The Python one is currently broken ("RuntimeError: maximum recursion limit 
exceeded").  I don't know enough about yapps to know how to avoid it - it used 
to work!

	Andy

> 
> Yosi, what's the status of N3 parsers based on n3.n3? Do they
> work yet? What about using that approach for the SPARQL parser?
> 
Received on Wednesday, 8 February 2006 16:09:42 GMT

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