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Re: Next telecon features & beyond

From: Lee Feigenbaum <lee@thefigtrees.net>
Date: Fri, 13 Mar 2009 15:36:27 -0400
Message-ID: <49BAB5BB.3040809@thefigtrees.net>
To: Alexandre Passant <alexandre.passant@deri.org>
CC: SPARQL Working Group <public-rdf-dawg@w3.org>
Alexandre Passant wrote:
> 
> Without any pathLength filtering, the query is simply a property path 
> query as proposed in [3], but that way of using a variable (rather than 
> including the regexp directly as in ":foo rdf:type/rdfs:subClassOf* 
> :bar") allows imho more extensibility, especially for that length feature.

Right, but [3] doesn't include variables in the path position. Putting 
my implementer's hat on, I think that allowing path variables is 
significantly more challenging to implement, so much so that I'd prefer 
to consider the two cases separately.

I'm happy to be convinced otherwise thogh :-)

Lee

> 
> Cheers,
> 
> Alex.
> 
> [1] 
> http://www-sop.inria.fr/edelweiss/software/corese/v2_4_1/manual/next.php
> [2] http://www.w3.org/2009/sparql/wiki/Feature:PathLength
> [3] http://www.w3.org/2009/sparql/wiki/Feature:PropertyPaths
> 
>> My understanding is that property paths allow me to specify in a 
>> regular expression-like way an explicit chain that connects two nodes. 
>> For path length, you need to start having variables match 
>> arbitrary-length paths between nodes, right? (Once you ahve a variable 
>> matching a path, then it's natural to add a function to get the length 
>> of that path.) And that seems like a whole other ball of wax to me.
>>
>> Am I misunderstanding?
>>
>> Lee
> 
Received on Friday, 13 March 2009 19:37:19 GMT

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