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[closed] reagle-01 reagle-02 XMLLiterals and exc-c14n

From: Jeremy Carroll <jjc@hpl.hp.com>
Date: Fri, 4 Apr 2003 23:55:58 +0300
To: www-rdf-comments@w3.org, reagle@w3.org, eric@w3.org, hendler@cs.umd.edu
Message-Id: <200304042355.58319.jjc@hpl.hp.com>

Comments accepted.

Joe, Jim, Eric,

You made last call comments concerning the treatment of 
rdf:parseType="Literal" and datatype rdf:XMLLiteral in the RDF Last Call 
Working Drafts.

  http://www.w3.org/2001/sw/RDFCore/20030123-issues/#reagle-01
  http://www.w3.org/2001/sw/RDFCore/20030123-issues/#reagle-02

Your emails raising the issue:

Joe's original mail:
  http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0335.html
Jim's mail on behalf of WebOnt
  http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0335.html
(see i.)
Eric's mail:
 http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0240.html

The RDF Core WG has resolved

http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Apr/0097.html
item 13,

to accept this issue and address it as proposed in
http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Mar/0151.html

I summarize that proposal here:

1: Only reference the exclusive canonicalization rec.
2: The syntax document specifies that the lexical form corresponding to the 
syntax rdf:parsetype="Literal"> XML content </ is the exclusive 
canonicalization with comments of that XML content. (With empty inclusive 
namespace prefix list)
3: The concepts document specifies 
   a corresponding lexical space
   a value space consisting of relevant exclusive canonical XML documents 
   a mapping function that is a simple string concatenation to wrap the XML 
element content in the lexical space with an rdf-wrapper start-element tag 
and end-element tag, with the xml:lang attribute, thus forming an exclusive 
canonical XML documents.
4. The semantics document follows the concepts document
5. the following implementation note is added to concepts:
[[
IMPLEMENTATION NOTE:
This section describes an *abstract* syntax which describes
equality of literals and equivalence of graphs. This is the
syntax over which the formal semantics are defined.
Implementations are free to represent literals and RDF graphs in
any other equivalent form.  As an example:
literals with datatype <tt>rdf:XMLLiteral</tt>s can be represented
in a non-canonical
format, and canonicalization performed during the comparison between two
such literals. In this example the comparisons may be
being performed either between syntactic structures or
between their denotations in the domain of discourse.
Implementations that do not require such comparisons can
hence be optimized.
]]

Jim,
I note you suggested
"An example fix would be to require an RDF/XML parser to use a specific 
canonicalization on input."
We stopped short of doing that because:
+ some RDF applications do not need this
+ the RDF documents do not define a processing model, and so do not define 
components such as RDF parsers
The implementation note above is thus a part of the resolution that you may be 
least confortable with.   

Please reply to this email, copying www-rdf-comments@w3.org indicating 
whether this decision is acceptable.

Joe, also note that we have not yet given detailed consideration to your 
comment "Confusion about wrapping of XMLLiteral"

http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0434.html

Now that we have removed all freedom in the syntax document, is this 
sufficiently clear (i.e. that the wrapping happens as part of the datatype 
mapping).
Or would you like us to consider that comment further?

Thankyou all for your comments that have helped us improve the RDF documents 
as part of the last call process.

Jeremy
Received on Friday, 4 April 2003 16:55:46 GMT

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