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Re: Changing @instanceof to @typeof

From: Mark Birbeck <mark.birbeck@x-port.net>
Date: Fri, 4 Apr 2008 16:33:38 +0100
Message-ID: <a707f8300804040833g6ccbff3dj1ef34c1b11b6f0b4@mail.gmail.com>
To: "Niklas Lindström" <lindstream@gmail.com>
Cc: "Ben Adida" <ben@adida.net>, "Elias Torres" <elias@torrez.us>, "Shane McCarron" <shane@aptest.com>, "public-rdf-in-xhtml-tf. w3. org" <public-rdf-in-xhtml-tf@w3.org>

Hi Niklas,

'is a' means something different to 'has', yet the RDF world carries
on, and nothing falls apart. :)

To be slightly more serious, RDF itself lends itself to many ways of
interpreting rdf:type. If we were very strict we would ignore all of
them, and say that there are no notions of objects, classes,
instances, etc., in RDF, and all we can say is that resource A has a
predicate rdf:type of B.

But of course it makes things a little easier if we treat rdf:type
specially. So we could say that when resource A has a predicate
rdf:type of B, it's convenient to express that in some other way, such
as:

 resource A is of type B;

 resource A is a B;

 resource A is an instance of B;

and so on.

But all of that is mere convenience; as far as RDF is concerned, we
have nothing other than a plain, ordinary:

 resource A has a predicate rdf:type of B

In other words, I think we're justified in calling this *mapping*
whatever we want, as long as it provides something that feels
consistent and meaningful to the our audience, since it has no basis
in RDF, and is only a mapping.

I believe @typeof, @instanceof, @kind, @kindof, @class, @a, @isa, and
lots more, are all reasonable candidates for expressing this mapping.
But since, if we're honest, none of them leap out as being the perfect
solution, we're left trying to choose the least confusing. :)

Regards,

Mark

On 04/04/2008, Niklas Lindström <lindstream@gmail.com> wrote:
>
>  Hello,
>
>  is it only me (and Ralph it seems in the minutes) who find @typeof
>  directionally wrong? Why not @oftype or @hastype?
>
>  A superficial reading make it seem as "instance" was replaced by its
>  exact inverse: "type", which obviously cannot mean the same thing. Or
>  am I just misinterpreting how @typeof should be read?
>
>  (Part of the thinking of "instanceof" was based on the N3 shorthand
>  "is ... of", which is N3:s version of @rev. N3 also has "has" as
>  syntax sugar for e.g. '<#me> has foaf:name "Niklas".', why I suggested
>  @hastype last year [1]. Along with @a. ;) )
>
>  Best regards,
>  Niklas
>
>  [1] <http://lists.w3.org/Archives/Public/public-swd-wg/2007Jul/0148.html>
>
>
>
>
>  On Fri, Apr 4, 2008 at 2:32 AM, Ben Adida <ben@adida.net> wrote:
>  >
>  >  It was considered this morning, and it was outvoted.
>  >
>  >  -Ben
>  >
>  >
>  >
>  >  On Apr 3, 2008, at 5:16 PM, Elias Torres <elias@torrez.us> wrote:
>  >
>  >
>  > >
>  > > I had sent an email asking to consider @kind as it picked up more
>  > interest.
>  > >
>  > > Is it too late? or did it get rejected at one of the meetings?
>  > >
>  > > -Elias
>  > >
>  > > On Apr 3, 2008, at 5:58 PM, Shane McCarron wrote:
>  > >
>  > > >
>  > > > As per my action item earlier today, I have updated the editors draft to
>  > reflect the resolution that the name @instanceof be changed to @typeof.  I
>  > have also updated the DTD.  Note that until implementations and the test
>  > cases are updated, things will not validate!
>  > > >
>  > > > Draft is at http://www.w3.org/MarkUp/2008/ED-rdfa-syntax-20080403/
>  > > >
>  > > > --
>  > > > Shane P. McCarron                          Phone: +1 763 786-8160 x120
>  > > > Managing Director                            Fax: +1 763 786-8180
>  > > > ApTest Minnesota                            Inet: shane@aptest.com
>  > > >
>  > > >
>  > > >
>  > > >
>  > >
>  > >
>  > >
>  >
>  >
>
>


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Received on Friday, 4 April 2008 15:34:22 UTC

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