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Re: #foo URI references

From: Graham Klyne <GK@ninebynine.org>
Date: Tue, 01 Jul 2003 15:41:45 +0100
Message-Id: <>
To: www-archive <www-archive@w3.org>

[Copy of message sent to Martin Duerst]


Sure, but this starts to look like "overloading" to me.

I think these are exactly two cases that might be best handled separately.

The trouble with recommending namespace declaration sis that they apply 
*only* for properties.  rdf:ID, rdf:about and rdf:resource don't recognize 
qname syntax (much as we might wish they did ... RDFcore slightly 
considered this and decided it was out-of-charter).


At 15:03 30/06/03 -0400, you wrote:

>I think I didn't give my whole story. I think what I said
>below applies one specific use of base, which is quite
>usual for HTML, but not for other uses.
>Basically HTML <base> or xml:base can be used for two purposes:
>1) To indicate the actual base URI of the current document.
>    This is helpful in certain mirroring situations, in off-line
>    editing/processing, and so on.
>2) To indicate any kind of base to shorten URIs, completely
>    independent of the original location of the current document.
>In HTML, because there is only one <base>, usage 1) is often
>predominant. But there are exceptions. For example I have used
><base> on a page with test links to the RDF validator
>(see http://www.w3.org/2002/08/rdf-i18n-tests/). In that case,
><base> came in very handy to shorten the URIs, and even more
>handy because it easily allowed to switch between a test instance
>of the validator and the production instance without having to
>change dozens of links.
>For xml:base, the situation may be a bit different because
>xml:base can be used repeatedly in an XML document. Also, we
>have to take into account the (somewhat arbitrary) definition
>of how xml:base interacts with external entities.
>Both HTML and RDF mainly look at 1) when defining how they
>want to behave fragments that refer to the current document.
>And the two things they want to do, namely a) knowing what the
>current document's original address was (RDF) and b) making
>sure that there is no unnecessary retrieval operations (HTML)
>are not in conflict as long as we are dealing with 1).
>My guess is also that 2) is not really used with same-document
>references. Definitely in my testing example, it wouldn't make
>sense. Probably RDF could explicitly discourage the use of
>xml:base for shortening URIs by recommending that suitable
>namespace declarations can be used.
>Regards,    Martin.

Graham Klyne
PGP: 0FAA 69FF C083 000B A2E9  A131 01B9 1C7A DBCA CB5E
Received on Tuesday, 1 July 2003 12:02:18 UTC

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