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✅ Literals as subjects Re: Toward easier RDF: a proposal

From: Tim Berners-Lee <timbl@w3.org>
Date: Thu, 22 Nov 2018 12:59:58 +0000
Message-Id: <F8B9DD9B-3B5B-4E15-A86D-064F12D39CA5@w3.org>
Cc: SW-forum Web <semantic-web@w3.org>, Dan Brickley <danbri@google.com>, "Sean B. Palmer" <sean@miscoranda.com>, Olaf Hartig <olaf.hartig@liu.se>, Axel Polleres <axel@polleres.net>
To: David Booth <david@dbooth.org>


> On 2018-11 -21, at 22:40, David Booth <david@dbooth.org> wrote:
> 
> 7. Literals as subjects.  RDF should allow "anyone to say
> anything about anything", but RDF does not currently allow
> literals as subjects!  (One work-around is to use -- you guessed
> it -- a blank node, which in turn is asserted to be owl:sameAs
> the literal.)  This deficiency may seem unimportant relative
> to other RDF difficulties, but it is a peculiar anomaly that
> may have greater impact than we realize.  Imagine an *average*
> developer, new to RDF, who unknowingly violates this rule and
> is puzzled when it doesn't work.  Negative experiences like
> that drive people away.  Even more insidiously, imagine this
> developer tries to CONSTRUCT triples using a SPARQL query,
> and some of those triples happen to have literals in the
> subject position.  Per the SPARQL standard, those triples will
> be silently eliminated from the results,[13] which could lead
> to silently producing wrong answers from the application --
> the worst of all possible bugs.
> 

Agreed.

I thought we had fixed that in some later spec but I guess not.

All code I have written, like cwm and rdflib.js, allows the same things in subject and object positions.  Life is too short for arbitrary unnecessary asymmetry.

timbl


Received on Thursday, 22 November 2018 13:00:05 UTC

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