FW: Input sought on datatyping tradeoff

see end for comments most appropriate to RDF
----- Original Message -----
From: "Jonathan Borden" <jonathan@openhealth.org>
To: "Drew McDermott" <drew.mcdermott@yale.edu>; <www-rdf-logic@w3.org>
Sent: Monday, July 15, 2002 9:21 AM
Subject: Re: Input sought on datatyping tradeoff

> Drew McDermott wrote:
> >
> > I know it is futile to make the point at this late date, but the whole
> > farcical question stems from the fact that RDF (and XML, and SGML, the
> > whole ridiculous lineage) have no syntax for string literals.  If
> > everything is a string, then nothing is a string.  The problem could
> > be solved very simply if every literal found in an RDF file belonged to
> > at most one literal class (some apparent literals being ill-formed,
> > and hence not belonging to any).  That would require strings to be
> > indicated in some explicit way.  Hey, about quotes?
> I understand your arguments but you are not giving SGML nor XML a fair
> evaluation.
> SGML has mandatory schema (called DTD) which is capable of assigning
> unabmiguous datatypes to essentially every syntactic structure ... such
> facilities are called NOTATIONs, Groves as well as an ability to specify
> delimiter characters (e.g. '<' and '>' are not intrinsically 'special' as
> far as SGML is concerned).
> SGML has had success in specifying precise documentation systems at very
> high expense for very large customers. XML was conceived as an attempt to
> _simplify_ SGML for mass market use and to some extent it has succeeded
> (mass market use, but not simplification :-))
> So there are lots of facilities in both SGML and XML that have not
> widespread use (e.g. NOTATIONS).
> Now XML Schema has been introduced to 'make up' for the shortcomings of
> in regard to datatypes in the absense of NOTATIONs and DTDs.
> If one _requires_ an XML Schema (or a RELAXNG schema for that matter), one
> can simply and unambiguously have _datatypes_ in XML documents. Such
> datatypes are delimited by markup not quotes -- no biggie.
> e.g.
> <ex:foo xsi:type="xsd:integer">10</ex:foo>
> Now you may not like the syntax, nor like XML Schema, but let's not argue
> about that because it is _another argument_. The _problem_ is not that XML
> has ambiguous syntax rather that _the type of XML_ that RDF uses does not
> adequately provide for such syntax. Namely RDF and XML Schema are not
> entirely compatible, e.g. it is not possible to write a complete RDF
> specification using XML Schema etc.
> ...
> >
> > Only because of XML absurdity, which has carried over to N3.
> ...
> >
> > I'm sorry to indulge in a bit of sarcasm here and there, but the
> > persistent desire of the Web community to shoot itself in the foot
> > over this issue, nay, saw its foot off inch by bloody inch, baffles
> > me.
> Well, the problem is that _different parts_ of the Web community are going
> off and doing incompatible things, e.g. the 'solution' that XML Schema has
> come up with is not entirely compatible with RDF, and there are many many
> other examples of such issues. But that is life I suppose.
> I suggest that RDF drop this issue for the moment, because a _proper
> treatment_ will likely require changes to the RDF syntax (as Drew points
> out) which would be most appropriately done in RDF 2 (during which RDF 2
> XML Schema 2 could be properly aligned for example)
> Jonathan

Received on Monday, 15 July 2002 09:38:38 UTC