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Re: around the table on datatypes [ was: Re: datatyping draft 3 (for telecon)]

From: Jan Grant <Jan.Grant@bristol.ac.uk>
Date: Tue, 19 Feb 2002 10:25:39 +0000 (GMT)
To: Brian McBride <bwm@hplb.hpl.hp.com>
cc: Pat Hayes <phayes@ai.uwf.edu>, w3c-rdfcore-wg <w3c-rdfcore-wg@w3.org>
Message-ID: <Pine.GSO.4.44.0202190958170.15622-100000@mail.ilrt.bris.ac.uk>
On Mon, 18 Feb 2002, Brian McBride wrote:

> At 23:58 14/02/2002 -0500, Pat Hayes wrote:
> >Latest version of the datatype summary document now available at
> >
> >http://www.coginst.uwf.edu/users/phayes/DatatypeSummary3.html
> >
> >incorporating ideas arising from discussions with Patrick S. (rdfs:drange
> >and especially section 10).
>
> I would like to "go round the table" of the WG on the latest datatype
> proposal.  By go round the table, I mean to solicit the views of each
> member of the WG, without initiating a debate on members views.  We can
> then summarize those views and deal with issues arising.
>
> Please answer the following questions:
>
>    o Does the datatyping proposal meet your
>      needs and the needs of your users?
>      (Who are they?) (What is missing?)

Yes, in that (as far as I can tell) I can attach datatypes to literals.
(I think some practical examples showing how to go about handling
literal enum types might be helpful; I'd like to see the other "use
cases" which Sergei collected and which Graham and others contributed
large lists of things to worked out both from the instance and the
schema specification point of view)

>    o Are there features that could be dropped and
>      still meet the needs of your users? (Which?)

Of the datatyping options presented, I prefer the doublet approach, for
what it's worth.

>    o Does the proposal 'work for you'?

As clean as the resulting MT may be, I still find this construction
ugly.

>    o Are there any concerns with the proposal
>      you would like to raise? (What are they?)

While I don't share DanC's worldview about what a literal is, S-b (of
some kind) needs support. If you accept the worldview that comes with
this proposal, then that's fine - but the existence of this won't stop
any of the bad modelling that's already going on. I'm kind of concerned
that we've got to sell a construct like this to the RDF world. I think
we may be sowing confusion.

I'm concerned that the focus of literals is on printable forms, not
values; the former ought to be solely the concern of a parser. However,
a "fix" to this would involve a bunch of things including syntax
support, which I don't think we could swing in RDF 1.0x.

The light I see at the end of the tunnel is the bottom half of Pat's
first figure:

	http://www.coginst.uwf.edu/users/phayes/dtypeFigDoublet.png

where the integer (not the numeral) 35 appears in the graph. This
looks like a diagram produced by an enlightened mind - as long as we
don't rule out the possibility of doing something like this (maybe in a
future spec?) I'd be happy.


-- 
jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
Tel +44(0)117 9287088 Fax +44 (0)117 9287112 RFC822 jan.grant@bris.ac.uk
"NOP" is a trivial implementation of an executable Z subset.
Received on Tuesday, 19 February 2002 05:27:16 EST

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