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RE: ISSUE-76: If we fixed namespaces, does RDFa still have problems?

From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Date: Tue, 15 Dec 2009 04:15:01 +0100
To: "Ennals, Robert" <robert.ennals@intel.com>
Cc: Toby Inkster <tai@g5n.co.uk>, Maciej Stachowiak <mjs@apple.com>, "public-html@w3.org" <public-html@w3.org>
Message-ID: <20091215041501411889.d1509244@xn--mlform-iua.no>
W.r.t. to your namespace proposal, then it would also have effect, I 
suppose, for XHTML+RDFa documents served as text/HTML:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" 
      "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd">

Since your proposal wants to avoid the indirection, what happens to the 
semantics of such a document, served as text/HTML, if it "breaks" your 
rules e.g. by binding the same prefix to different namespaces? 

Instead of trying to establish default prefixes for code from other 
specifications via a registry, why not rather focus on 
prefixes/solutions for the (X)HTML namespace? E.g. Microdata consists 
of a specification and some vocabularies. I think, to make RDFa 
"native" to HTML and simple to use, then a vocabulary for the HTML 
namespace could be useful. 

It should be simpler to use this vocabulary than other vocabularies. 
Either because it could be used without any prefix at all. Or, at least 
because the HTML prefix for use with the vocabulary would not be 
necessary for the author to declare. One could also forbid to register 
_this_ prefix to any other namespace. Foreign namespaces in HTML 5, 
such as SVG and MathML, should also ideally be "preloaded" with this 
prefix/vocabulary, so that one could use it there too, without 
declaring it.

These HTML namespace vocabularies would then also be possible to use 
not only in HTML documents, but also in other mark-up languages.

Leif Halvard Silli

Ennals, Robert, Mon, 14 Dec 2009 22:51:34 +0000:
> Indeed.
> 
> One of the key ideas in my namespace proposal is that prefixes that 
> are likely to be used widely and are subject to a name clash must be 
> registered. This allows everyone to use the same prefix while knowing 
> that it can only mean one thing.
> 
> The "x-" prefix is only used for prefixes that have not been 
> registered, either because they are experimental, or intended only 
> for use within a single organization. End users should use "x-" 
> prefixes rarely, if at all, and a validator should warn if they are 
> being used.

>> From: Toby Inkster [mailto:tai@g5n.co.uk]

>>> saying what “x-apple” means.
>> 
>> Given that the name "Apple" was recently subject to an enormous lawsuit
>> between Apple Records and Apple Computers, surely this shows precisely
>> why this couldn't work?
>> 
>> A registration authority is needed to ensure uniqueness of name. RDF
>> uses URIs, and thus piggybacks on top of a registration authority which
>> has proved itself to be pretty good: the DNS.
-- 
leif halvard silli
Received on Tuesday, 15 December 2009 03:15:50 UTC

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