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Re: Issue http://www.w3.org/2000/03/rdf-tracking/#rdf-ns-prefix-confusion

From: Graham Klyne <Graham.Klyne@Baltimore.com>
Date: Thu, 24 May 2001 16:09:38 +0100
Message-Id: <5.0.2.1.2.20010524160432.039218e0@joy.songbird.com>
To: Dave Beckett <dave.beckett@bristol.ac.uk>
Cc: w3c-rdfcore-wg <w3c-rdfcore-wg@w3.org>
Dave, mostly looks good, I think.  Two questions/comments.

(1)

>I've tried to capture the concensus on deprecation but I'm unsure if
>it comes across in the above.  Specifically, #3 and #4 seem to
>clash.  Do we allow unprefixed attributes for backwards comp. at all
>in future or forbid them in the future?

I think #4 and #5 together capture the issue for the current specification 
rev.  We can leave future  "generations" free to make the requisite choices 
for future spec revisions.  I think #3 could be dropped.


(2)

>7.  Unprefixed attributes not on The List have no meaning in RDF
>     and MUST NOT be used to generate statements.   Applications MUST
>     skip the element containing such attributes and generate no
>     statements for the entire XML element and content.

The first sentence of this is fine.  I'm not sure of the implications of 
the second sentence.

#g
--

At 02:47 PM 5/24/01 +0100, Dave Beckett wrote:

>Previous threads can be followed from
>   http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/0087.html
>
>I propose we resolve:
>
>1. The current RDF/XML syntax uses the following attributes in the syntax:
>
>      about aboutEach aboutEachPrefix
>      ID bagID
>      resource
>      parseType
>      -- List of RDF attributes (henceforth The List)
>
>      The remaining concepts are not in the list because:
>        a. Seq Bag Alt Property Statement
>         These are rdfs:Class-es and can never be used as attributes
>        b. RDF Description
>         Syntax only things that have no current use as attributes
>        c. li _<n> subject predicate object type value
>         Not allowed to be used unprefixed according to the grammar
>
>      Note Re: aboutEach aboutEachPrefix
>        At present it is expected these will be removed from the
>        specification although the WG has not addressed this yet.
>        See thread at 
> http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001May/0123.html
>
>2.  The grammar will be corrected to require namespace-qualification
>     for all attributes for The List.  A namespace prefix MUST be used
>     for these attributes, where the namespace prefix points to the
>     RDF URI http://www.w3.org/1999/02/22-rdf-syntax-ns#
>
>     The meaning of the attributes is defined by the appropriate RDF
>     M&S sections and is not modified here.
>
>     The changes to the grammar at
>       http://www.w3.org/TR/REC-rdf-syntax/#grammar
>     include modifying productions 6.6, 6.7, 6.8, 6.9, 6.11, 6.18,
>     6.32, 6.33 to have rdf: added before all the attributes.  There
>     are almost certainly other changes to the grammar, as well as
>     changes throughout the rest of the document such as examples and
>     in-text mentions.
>
>3.  Unprefixed attributes are deprecated - they SHOULD NOT be used in
>     the syntax from this date and WILL be forbidden in the next RDF
>     syntax document.
>
>4.  On input, unprefixed attributes from The List MAY be accepted.
>     If accepted, these attributes MUST be handled as if they were
>     written with a prefix as defined in #2.
>
>5.  On output, all RDF attributes from The List MUST be emitted with
>     a namespace prefix; where the prefix is defined as in #2.
>
>6.  The grammar will be corrected to allow non-namespace
>     qualified RDF elements (NOT attributes) when a default XML
>     namespace is defined with an xmlns="..." attribute.
>
>     Discussion: For example
>       <Description xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
>          ...
>       </Description>
>     is currently forbidden by production 6.3; it requires rdf:Description
>
>7.  Unprefixed attributes not on The List have no meaning in RDF
>     and MUST NOT be used to generate statements.   Applications MUST
>     skip the element containing such attributes and generate no
>     statements for the entire XML element and content.
>
>I've tried to capture the concensus on deprecation but I'm unsure if
>it comes across in the above.  Specifically, #3 and #4 seem to
>clash.  Do we allow unprefixed attributes for backwards comp. at all
>in future or forbid them in the future?
>
>Dave

------------------------------------------------------------
Graham Klyne                    Baltimore Technologies
Strategic Research              Content Security Group
<Graham.Klyne@Baltimore.com>    <http://www.mimesweeper.com>
                                 <http://www.baltimore.com>
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Received on Thursday, 24 May 2001 12:15:43 EDT

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