- From: Danny Ayers <danny@panlanka.net>
- Date: Fri, 20 Apr 2001 20:19:30 +0600
- To: "Lee Jonas" <lee.jonas@cakehouse.co.uk>, "Murray Altheim" <altheim@eng.sun.com>
- Cc: "RDFInterest" <www-rdf-interest@w3.org>, "Brian McBride" <bwm@hplb.hpl.hp.com>
I can't see how RDF could be practical without some mechanism for inherited/shared metadata (you've got a 1000 documents with the same author - do you need to specify this a 1000 times), but I'm thinking that because this is so significant it must have been dealt with already - seeAlso doesn't really seem adequate, I'm not sure of the history of aboutEachPrefix, but surely there is already some mechanism in place? Lee's xsl:include/import suggestion sounds possible. If this angle is well covered, an idiot's guide is needed (for this idiot at least), otherwise I think it could well be an issue. --- Danny Ayers http://www.isacat.net <- -----Original Message----- <- From: www-rdf-interest-request@w3.org <- [mailto:www-rdf-interest-request@w3.org]On Behalf Of Lee Jonas <- Sent: 20 April 2001 19:47 <- To: 'Danny Ayers'; Murray Altheim <- Cc: RDFInterest <- Subject: RE: RDF in XHTML <- <- <- <- <- Danny Ayers [mailto:danny@panlanka.net] wrote: <- <- ><- The RDF Schema spec hints at 'rdfs:seeAlso' for cascading purposes, <- e.g.: <- ><- <- ><- <rdf:RDF ...(namespaces)...> <- ><- <rdf:Description rdf:about="" rdfs:seeAlso="furtherinfo.rdf"/> <- ><- </rdf:RDF> <- > <- >Looks viable - I wonder if there's anything more than hints <- >this is rather important, probably well known (but I can't <- think of it) - <- >what is the best way to use inheritance of metadata between documents? <- >How do I avoid adding the same author information to every one of the <- >million pages I've written (with the aid of some monkeys)? <- > <- <- Well, this is an entirely different prospect, and one I think that the <- 'rdf:aboutEachPrefix' predicate was intended to address. <- However, AFAIK it <- has a lot of opposition due to the fact that it is difficult to <- implement in <- practise, e.g.: <- <- 1) Consider starting with a resource and trying to determine who <- the author <- was. If this info is in a 'rdf:aboutEachPrefix' statement in <- some other rdf <- doc, not even referenced from the resource you are currently <- processing, it <- is nigh on impossible to determine. <- <- 2) It relies upon the hierarchical location of resource representations - <- the granularity of what these kinds of statements apply to is <- too course - <- i.e. all resources whose URIs 'startWith' a common substring. It <- might have <- been better to do something akin to what XPointer does for XML. <- <- Suggestion: <- IMHO rdf:seeAlso is equivalent to xsl:include semantics. What <- is lacking is <- xsl:import semantics. The latter might allow you to define a set of <- statements that apply to their current doc, then 'importing' <- that doc from <- another would make those same statements apply to the doc doing the <- importing. Hence, importing a handful of rdf docs containing common <- statements (e.g. author) from a million XHTML web pages would <- save a lot of <- typing! <- <- This would solve both 1) and 2) above to some degree of <- satisfaction - the <- degree of satisfaction of 2) depends on how you structure your imported <- docs. Is this worthy of the issues list? <- <- > <- > <- ><- >On another line, forget XHTML for a moment, how do we embed <- metadata in <- ><- >other XML markups? <- ><- <- ><- I thought this is what XML Namespaces are for! Just embed your <- elements, <- ><- any processor that doesn't recognise the namespace (within its <- ><- context) can <- ><- ignore it. Note that to validate such documents properly (and allow <- such <- ><- open mixing-and-matching of different 'XML mini-languages') will <- ><- require XML <- ><- Schema. <- > <- >Quite. (to avoid this going in circles, please ignore) so why <- should XHTML <- >be treated any different? <- <- One reason is that it is currently validated using a DTD. Whether XML <- Schema would fare better, I don't altogether know for sure. <- <- (Note that my current understanding of XML Schema is not perfect, I am <- hoping that XML Schema allows you to freely mix-and-match elements in <- different XML namespaces.) <- <- regards <- <- Lee <-
Received on Friday, 20 April 2001 10:24:10 UTC