Re: A simple question....

I would like to continue the discussion. Comments below.

Pierre-Antoine CHAMPIN wrote:
> 
> > Any given implementation will only support a subset of all the types
> > of URIs. It could know what types it can retrieve, what types
> > represent "the outside world", etc. But new types could be
> > invented. Previously unaccessible objects, like bar-code numbers,
> > could be made accessible by a new internet service, giving metadata
> > about the product.
> 
> Yes, but you will never get the product !
> The codebar URI can identify a product, since there is a one-to-one relation
between them,
> but it can't dereference to the product itself, only to information about it.
> So I think the important thing is to make the difference between
> 
>  * URI we use to identify a piece of (meta)data (retrievable or not)
> 
>  * URI we use to identify a 'real' object,
>    and which can perhaps be dereferenced to some metadata ABOUT that object.
> 
> I guess this is application dependant :
> some application will be interested in the sociol security file of a person,
> so the SSN-schema URIs will be in the first category above ;
> some other could use the SN-schema to identid=fy persons, in which case
> these URIs will be in the second category.


With schemas, you could specify that an URI is an instance of some
type.  Literals is said to be an instance of the Literal class. You
can subclass the literal class and set the type of the URI to be a
specific type of value.

I think that is the better way to do it. If no type is present, the
application would have to guess.



-- 
/ Jonas  -  http://paranormal.o.se/perl/proj/rdf/schema_editor/

Received on Sunday, 5 December 1999 09:04:29 UTC