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Re: Simple solution? Pub. Idents. vs URN.

From: Paul Prescod <papresco@calum.csclub.uwaterloo.ca>
Date: Wed, 27 Nov 1996 14:54:15 -0500
Message-Id: <1.5.4.32.19961127195415.009336e8@csclub.uwaterloo.ca>
To: dgd@cs.bu.edu (David G. Durand), w3c-sgml-wg@w3.org
At 02:38 PM 11/27/96 -0500, David G. Durand wrote:
>><!ENTITY open-hatch
>>        PUBLIC "ISO .... "
>>"http://www.textuality.com/boilerplate/OpenHatch.xml">
>>
>>then we preserve the essential internet-centricity and usability of XML, but
>>allow the traditional SGML "escape hatch" for people who want to
>
>This is acceptable, but making the system identifier mandatory is a shame
>given that it is the _optional_ FPI that is the persistent identifier. 

Not all documents will have persistent identifiers. But all documents *will*
have locations. (just as all machines do not have domain names, but all
machines do have IP addresses) We would give the FPI "dominance" over the
SYSTEM identifier, if the XML processor thought it knew how to resolve it.

>I'd
>be happier if I could stop using URLs the _instant_ it was feasible.
>Allowing URNs as system IDs seems a way to accomplish that.

There will be a transition period. Don't you find you occaisionally still
have to type IP addresses out, or see them pop up in your browser? How do
you decide when it is "feasible?" And, more important, why not begin putting
persistent names in your documents now, with the understanding that the
technology to seamlessly handle them is coming.

I think it is a good idea to provide a direct pointer to the real object as
a backup, anyhow. I suspect that URN resolvers will break down sometimes...

>   My XML parser can always implement catalogs by looking for URN syntax in
>the sytem ID, and doing something sensible.

As long as you don't want to use those documents with next year's batch of
XML browsers, which will not understand URN syntax (unless we intend to
preemptively standardize it).

 Paul Prescod
Received on Wednesday, 27 November 1996 14:52:50 EST

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