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Re: URIs-Resource relationships

From: John Cowan <jcowan@reutershealth.com>
Date: Thu, 07 Sep 2000 13:12:01 -0400
Message-ID: <39B7CC61.AC197208@reutershealth.com>
To: liberte@crystaliz.com, "xml-uri@w3.org" <xml-uri@w3.org>
liberte@crystaliz.com wrote:
>
> What we need is a way of specifying things such as the following:

(dum dum dum) Hello Frege / hello Russell / Here we are at / Camp Befuddle ...
 
> * A specific set of URIs that all map to the same resource by some
>   measure of equality.
> 
> * A general set of URIs, or URI patterns, that may be assumed to
>   map to the same resources.  e.g. "case doesn't matter for us"

These can be achieved by defining "=" for resources.  Just as 2+2 = 4
means that the referent of the expressions "2+2" and "4" are the
same object (is the same object?), so the same can apply to
ftp://ftp.unicode.org/Public and http://www.unicode.org/Public,
both of which are directory resources.  Note that "=" is just the
smallest equivalence relationship between resources as between
numbers; you don't need to talk about relationships between URIs
as such at all.

However, it still seems to be official that the relation between
URIs and resources is an isomorphism.

> * URIs that are mapped to no internet representation but still
>   somehow identify an abstract resource.

No special situation:  urn:isbn:1565921496 refers to the 2nd edition
of the Camel Book, which has no Internet representation.

> * Resources that are associated with multiple entities, which may
>   or may not have their own URIs.

That is content negotiation.
 
> * Resources that are collections of other resources.
> 
> * Resources that "contain" other resources.
> 
> * Resources that will always have only one bit representation.

These are ordinary resource properties, not properties of URIs.
 
-- 
There is / one art                   || John Cowan <jcowan@reutershealth.com>
no more / no less                    || http://www.reutershealth.com
to do / all things                   || http://www.ccil.org/~cowan
with art- / lessness                 \\ -- Piet Hein
Received on Thursday, 7 September 2000 13:12:06 GMT

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