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[Core] Lists - change vote to abstain

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Thu, 16 Apr 2009 08:32:39 +0100
Message-ID: <49E6DF17.3020909@hplb.hpl.hp.com>
To: RIF WG <public-rif-wg@w3.org>
I meant to abstain on last night's vote on lists (I claim befuddlement 
due to anti-social hours :-)). This doesn't change the outcome at all 
but I wanted to formally register my reasons for abstaining.

Lists are clearly useful and used in most production rule and LP engines 
so having them in both PRD and BLD and thus in Core makes sense.

However, for RDF rule engines including Jena (and I believe CWM and 
Euler) there is a small problem. We already have lists but they are RDF 
lists. An RDF engine shouldn't implement RIF lists by translating them 
to RDF lists because that would generate additional frame entailments.

Technically it would be a small matter to extend such systems to 
implement RIF lists as well, it violates "implement by translation" but 
we've violated that already.  However, from a user viewpoint this would 
be a problem - there would now be two different list constructs with 
different characteristics and we know that anything that confuses users 
leads to support costs (much more important than implementation costs).

Thus there is a risk that Jena would not implement these Lists or would 
do so via translation to RDF lists and either way would not be a 
candidate Core implementation.

C'est la vie

Dave
Received on Thursday, 16 April 2009 07:33:24 GMT

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