Re: xml:lang [was Re: Outstanding Issues ]

At the risk of further complicating this discussion, let me give my
interpretation, for what it's worth, of the M&S material in question,
i.e.,

[[ (P221) The xml:lang attribute may be used as defined by [XML] to 
associate a language with the property value. There is no specific data 
model representation for xml:lang (i.e., it adds no triples to the data 
model); the language of a literal is considered by RDF to be a part of
the 
literal. An application may ignore language tagging of a string. All RDF 
applications must specify whether or not language tagging in literals is 
significant; that is, whether or not language is considered when
performing 
string matching or other processing.]]

I'd first observe that the XML spec cites as an example of using
xml:lang distinguishing between

<p xml:lang="en-GB">What colour is it?</p> and
<p xml:lang="en-US">What color is it?</p>

Then a few observations based on P221:

1.  "There is no specific data model representation for xml:lang (i.e.,
it adds no triples to the data 
model)".  That is, the lang attribute isn't explicitly reflected in the
"data model" *as triples*

2.  The problem is interpreting what "the language of a literal is
considered by RDF to be a part of the 
literal" means. Brian says it means that a literal is really
(effectively) a pair.  Patrick says the language is non-existent in the
RDF graph.

3.  P221 also says: "All RDF applications must specify whether or not
language tagging in literals is 
significant; that is, whether or not language is considered when
performing string matching or other processing."  [Note:  RDF
application, not XML application].  If the language tagging is not
available in what an RDF application processes, this doesn't appear to
make any sense;  the application would have nothing to consider.  If an
RDF application always processes an XML serialization, things would be
OK.  But if an RDF application only processes triples (not an XML
serialization), it seems to me we need to do one of two things:

a.  dispense with most, if not all, of P221:  not just the part that
says that the language is considered part of the literal, but also the
part that talks about RDF applications possibly considering language
tagging in string matching and other processing.

b.  accept that the language information is *somehow* there in the
literal (although the M&S doesn't say how).  Effectively, that sounds
like a pair.

[actually, maybe there's a c.:  change what we mean by "RDF
application")

--Frank




-- 
Frank Manola                   The MITRE Corporation
202 Burlington Road, MS A345   Bedford, MA 01730-1420
mailto:fmanola@mitre.org       voice: 781-271-8147   FAX: 781-271-8752

Received on Tuesday, 12 February 2002 13:32:41 UTC