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RE: first pass parseType="Literal" text for primer

From: Graham Klyne <gk@ninebynine.org>
Date: Mon, 28 Jul 2003 14:01:58 +0100
Message-Id: <5.1.0.14.2.20030728135935.025807b8@127.0.0.1>
To: <Patrick.Stickler@nokia.com>, <w3c-rdfcore-wg@w3.org>

Sounds about right to me.  Here's another case to consider:

   <title rdf:parseType='Literal'>Why the &lt;FONT> Tag is Bad</title>

which I understand to be valid XML, I think also yields:

   "Why the &lt;FONT&gt; Tag is Bad"^^rdf:XMLLiteral

(underscoring that the &-stuff in the XML lexical form is put there by the 
RDF parser handling the C14N stuff.)

#g
--

At 15:52 28/07/03 +0300, Patrick.Stickler@nokia.com wrote:

>OK.
>
>If I'm understanding this correctly, the &lt; and &gt;
>are getting resolved to '<' and '>' by the RDF/XML
>parser, insofar as the XML processing of the RDF/XML
>instance is concerned, but the canonicalization is
>re-escaping them back to &lt; and &gt;?
>
>If the entities are not ever being resolved at any
>stage of the parsing process, then that worries me
>alot. It suggests that an RDF/XML parser is not
>playing by the rules of XML fully.
>
>Patrick
>
> > -----Original Message-----
> > From: ext Graham Klyne [mailto:gk@ninebynine.org]
> > Sent: 28 July, 2003 15:13
> > To: Stickler Patrick (NMP/Tampere); w3c-rdfcore-wg@w3.org
> > Cc: Dave Beckett
> > Subject: RE: first pass parseType="Literal" text for primer
> >
> >
> > At 14:31 28/07/03 +0300, Patrick.Stickler@nokia.com wrote:
> >
> >
> >
> > > > 2. <title rdf:parseType='Literal'>Why the &lt;FONT&gt; Tag is
> > > > Bad</title>
> > > >
> > > > I take the value of this 'title' property to be:
> > > >
> > > >    "Why the &lt;FONT&gt; Tag is Bad"^^rdf:XMLLiteral
> > >
> > >Eh? Really?
> > >
> > >Don't you mean
> > >
> > >    "Why the <FONT> Tag is Bad"^^rdf:XMLLiteral
> > >
> > >Surely the entities are resolved the same as for any
> > >literal.
> >
> > Not by my reading of Concepts:
> >
> > [[
> > The lexical space
> >      is the set of all strings which:
> >
> >          * are well-balanced, self-contained XML data [XML];
> >          * correspond to exclusive Canonical XML (with
> > comments, with empty
> > InclusiveNamespaces PrefixList ) [XML-XC14N];
> >          * when embedded between an arbitrary XML start tag
> > and an end tag
> > form a document conforming to XML Namespaces [XML-NS]
> > ]]
> > --
> > http://www.w3.org/2001/sw/RDFCore/TR/WD-rdf-concepts-20030117/
> > #section-XMLLiteral
> >
> > which would require the '<' and '>' here to be &-escaped.
> > When the XML
> > literal is eventually interpreted, you'd get the bare '<' and '>'
> > characters back.
> >
> > [...removes sleeping cat from copy of syntax spec...]
> >
> > Looking at the syntax spec, struggling a bit...
> >
> > [Dave:  Should section "6.1.2 Element Event" be "Start
> > Element Event", and
> > should there be a description of what the "string-value" accessor
> > returns?  Maybe not, but I note section 6.1 says that all
> > events have a
> > string-value accessor.]
> >
> > Ah, got it:
> >
> > In the syntax spec, we have sections 7.2.17 and 7.2.33 which
> > together claim
> > the literal string value is the exclusive XML canonicalization of the
> > content, which I think means that the escaping of '&', '<'
> > and '>' has to
> > be re-inserted:
> >
> > [[
> > The string used as the lexical form of the XML Literal is the
> > Exclusive XML
> > Canonicalization [XML-XC14N]) with comments and with empty
> > InclusiveNamespaces PrefixList of the literal text l, i.e. the entire
> > element content of this property element.
> > ]]
> > --
> > http://www.w3.org/2001/sw/RDFCore/TR/WD-rdf-syntax-grammar-200
>30117/#parseTypeLiteralPropertyElt
>
>[Dave:  is it worth adding a note to clarify this point?]
>
>
>
> >If you wanted/needed
> >
> >     "Why the &lt;FONT&gt; Tag is Bad"^^rdf:XMLLiteral
> >
> >then you'd have to say
> >
> >   <title rdf:parseType='Literal'>Why the &amp;lt;FONT&amp;gt; Tag is
> > Bad</title>
> >
> >No?
> >
> >If this is not the case, then I've really missing something
> >major here and am very alarmed!
>
>I think that may be workable, but it's not how I read the documents we're
>working on.
>
>(Note that this formulation of the abstract syntax is for definitional
>purposes, and does not of itself require that an application do this.  You
>may have some other way of storing an XML literal which is fine as long as
>you get the same final answers.)
>
>#g
>
>
>-------------------
>Graham Klyne
><GK@NineByNine.org>
>PGP: 0FAA 69FF C083 000B A2E9  A131 01B9 1C7A DBCA CB5E

-------------------
Graham Klyne
<GK@NineByNine.org>
PGP: 0FAA 69FF C083 000B A2E9  A131 01B9 1C7A DBCA CB5E
Received on Monday, 28 July 2003 09:05:32 EDT

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