W3C home > Mailing lists > Public > public-rif-wg@w3.org > May 2008

Re: Consts/CURIEs in PS (was Re: DTB status (on today's agenda) )

From: Jos de Bruijn <debruijn@inf.unibz.it>
Date: Tue, 06 May 2008 14:22:36 +0200
Message-ID: <48204D8C.4000208@inf.unibz.it>
To: Michael Kifer <kifer@cs.sunysb.edu>
CC: Sandro Hawke <sandro@w3.org>, Axel Polleres <axel.polleres@deri.org>, "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>


Michael Kifer wrote:
>> Michael Kifer wrote:
>>> Cool!
>>>
>>> There is only one little thing. Right now the spec allows "aliases" for
>>> symbol space names. Those aliases are not required to be IRIs (otherwise I
>>> do not see a purpose for them). So, something like
>>>
>>> "abc"^^foobar&>%$
>>>
>>> is also possible (in principle). It would be wrong to write it as 
>>>
>>> "abc"^^<foobar&>%$>
>>>
>>> since foobar&>%$ is not an iri.
>>>
>>> On the other hand, I do not see those aliases as terribly useful in any
>>> form or shape. I included them because Jos wanted them. So, I would be
>>> perfectly happy to throw them out.
>> I think there was a misunderstanding.  I was only advocating the 
>> possibility of having aliases that are also IRIs.  (the reason for 
>> allowing aliases is compatibility with other semantic Web languages)
> 
> There are also languages where aliases are not IRIs.

Those can easily be exchanged as IRIs.

> I would then propose to get rid of the aliases, since it is not clear why
> they are needed in an exchange language.

I don't think we can really decide what is "needed".  I know that RDF 
and OWL, which are exchanged languages for data and ontologies, allow 
datatypes with multiple identifiers.  In addition, every XML schema 
datatype has 2 IRIs according to the specification [1].
Those would be 2 arguments for allowing multiple identifiers for a 
single datatype.

That said, I would not be totally against disallowing using multiple 
identifiers.  In that case, we would need to specify which identifiers 
people have to use for XML schema datatypes and explicitly state that 
they cannot use the other identifiers.

Best, Jos


[1] http://www.w3.org/TR/xmlschema-2/#namespaces

> 
> 
> 
> 	--michael  
> 
> 
>> Best, Jos
>>
>>>
>>> 	--michael
>>>
>>>
>>>> Okay, I think I see a consensus here (more or less proposed by Jos and
>>>> Michael at different times):
>>>> (1) "foo"^^<bar>
>>>>
>>>> This is the normal, full syntax for constants.  For example:
>>>>
>>>>     "http://purl.org/dc/terms/creator"^^<http://www.w3.org/2007/rif#iri>
>>>>
>>>> (2)  foo:bar    
>>>>
>>>> is shorthand for
>>>>
>>>>     "expand(foo)bar"^^<http://www.w3.org/2007/rif#iri>
>>>>
>>>> except on the right-hand-side of a ^^.
>>>>
>>>> (3) "foo"^^bar:baz
>>>>
>>>> is shorthand for
>>>>
>>>>     "foo"^^<expand(bar)baz>
>>>>
>>>> This means that the CURIE syntax (a:b) is context sensitive; it's read
>>>> differently on the right-hand-side of ^^.
>>>>
>>>> (4) <foo>
>>>>
>>>> This is not allowed.  The pointy-brackets are only allowed as part of
>>>> the ^^ construct. Maybe someday we can figure out a way to allow it, but
>>>> right now it has problems.
>>>>
>>>> (5) "foo"^^bar
>>>>
>>>> is allowed for aliasing (I don't quite follow this), but doesn't
>>>> interact with the above.
>>>>
>>>> ================================================================
>>>>
>>>> If I'm understanding everyone correctly, we can all live with that.
>>>> Yes?
>>>>
>>>>      -- Sandro
>>>>
>>>>
>>>>
>>>
>>>
>> -- 
>> Jos de Bruijn            debruijn@inf.unibz.it
>> +390471016224         http://www.debruijn.net/
>> ----------------------------------------------
>> An expert is a person who has made all the
>> mistakes that can be made in a very narrow
>> field.
>>    - Niels Bohr
>>
> 
> 
> 

-- 
Jos de Bruijn            debruijn@inf.unibz.it
+390471016224         http://www.debruijn.net/
----------------------------------------------
An expert is a person who has made all the
mistakes that can be made in a very narrow
field.
   - Niels Bohr


Received on Tuesday, 6 May 2008 12:22:50 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 2 June 2009 18:33:48 GMT