W3C home > Mailing lists > Public > public-rdf-wg@w3.org > November 2012

Re: Sloppy inference rules

From: Antoine Zimmermann <antoine.zimmermann@emse.fr>
Date: Thu, 01 Nov 2012 19:33:38 +0100
Message-ID: <5092C082.1040908@emse.fr>
To: Pat Hayes <phayes@ihmc.us>
CC: Ivan Herman <ivan@w3.org>, Markus Lanthaler <markus.lanthaler@gmx.net>, 'Guus Schreiber' <guus.schreiber@vu.nl>, 'RDF WG' <public-rdf-wg@w3.org>
Le 01/11/2012 17:43, Pat Hayes a écrit :


>> I can see this point. However, my understanding is that a number of
>> RDF environments, libraries, etc, have optimized along the lines of
>> those restrictions. Changing this, ie, removing the restrictions in
>> RDF 1.1, would lead to the necessity of major rewrites of existing
>> systems. I would expect that to be a big no-no.
> Yes, I think that is the reason for retaining the restrictions. The
> problem with that line of thinking, however, is that this kind of
> too-expensive-to-change argument only becomes stronger as time goes
> on, so changes will *never* get made. And the counterargument is that
> allowing newer implementations to be more accepting does not
> invalidate the older implementations or make them less able to do
> anything they can do now. It just means that they can no longer claim
> to be covering all of the (now larger) language, which means that the
> argument is basically not even technical, but has to do with
> corporate advertising and image.
> Pat


I just want to emphasise that when Pat says that adding literals as 
subject or bnode as predicate is not a problem at all in terms of 
semantics, it is not a guess made without consideration of the minute 
details (it is often the case that we make statements that do no 
consider all the subtle implications). It is *truly* a trivial change to 
the semantics, even when considering all the implications on OWL, RIF or 
all standards using RDF. If the RDF WG was required to remove the 
restrictions, it would take very little effort to update the documents.

The trouble is only due to syntaxes not having this already, and most 
importantly, implementations making optimisations based on the 
restrictions. W3C is very much concerned about current deployment, which 
is why it did not take the risk of broadening the syntax.
Antoine Zimmermann
ISCOD / LSTI - Institut Henri Fayol
École Nationale Supérieure des Mines de Saint-Étienne
158 cours Fauriel
42023 Saint-Étienne Cedex 2
Tél:+33(0)4 77 42 66 03
Fax:+33(0)4 77 42 66 66
Received on Thursday, 1 November 2012 18:34:49 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:04:22 UTC