- From: Bill de hÓra <dehora@eircom.net>
- Date: Tue, 12 Feb 2002 16:18:31 -0000
- To: "'RDF Core'" <w3c-rdfcore-wg@w3.org>
> From: Brian McBride [mailto:bwm@hplb.hpl.hp.com]: > > A good reason might have the form "If we do it as m&s says, > problem x occurs". This old thing again. Patrick, Jeremy and I did some work on this last year, it seemed to raise more problems than it solved and annoy more people than it was worth. If we stay as the M&S says, then I think we have an obligation to explain, 1) why the language is a part of a literal, and not say, a property of it (I think we know the answer to this, but we need to just come out and say it)? 2) what is meant by "part of"? 3) why only 2 parts? I don't think that composing a literal of (string, lang) pairs is a particularly good way of modelling a literal and I don't like giving language special status, but...my answers: 1) literals can't have properties, but we find xml:lang in the syntax very handy, so we made it part of a literal. 2) it means not a property of. 3) the lang part is the only property we think we need at the moment. Chances are future version of RDF will allow literals to have properties so don't sweat it. As an implementer, the para Brian took from the spec: [[ (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.]] needs to be fixed. There is no way specified way for an RDF application to signal whether lang tags are significant, specifying MUST here is ridiculous (what's an RDF application anyway?). Further, if language is part of a literal why can it be blissfully ignored (why can't I ignore the string). "An application may ignore language tagging of a string.": I mean what's a string here? The M&S just moves freely from literal as <string> with a language tag to literal as <string lang>. Please, we all know this is humbug and that lang is an odd man out; no-one's asking why the string is a part of literal. It's simply that the syntax is tied too closely to the model at this point in the M&S and the lang tag is an XML artefact that's crept into the graph. If we're keeping literals as (string lang) pairs, then at least remove the signalling constraint mentioned on applications, being not usefully enforceable or testable. Bill de hÓra
Received on Tuesday, 12 February 2002 11:23:30 UTC