- From: Ossi Nykänen <onykane@butler.cc.tut.fi>
- Date: Thu, 18 Sep 2003 12:34:02 +0300 (EEST)
- To: "Williams, Stuart" <skw@hp.com>
- Cc: www-tag@w3.org
My original "complaint" is that instead of (W3C) saying something like "sure -- you MAY invent any URI spelling (within your authority) as you wish", I would appreciate a more constructive statement like "yes, we are actually promoting consistent, long-term URI name bookkeeping (for denoting certain kinds of Web resources); here are guidelines how it could be done...". More formal the better. Some resources are to be scrapped or versioned for sure -- to me it would make lot of sense to (uniformly) recognise this at the Webarch level (a cheap way might be an add-on to the URI spelling; which of course is only one alternative). It might be a bit tricky, of course, but then, few things aren't. (Say, like profiling an ISO standard: now that's tricky.) On Wed, 17 Sep 2003, Williams, Stuart wrote: > ... > The content of an advertisment can change. > ... True, but there are two cases: 1) changing an "existing" advertisement A and 2) publishing a new one A' (and perhaps throwing the old advertisement A away). In other words, if the principle "Use URIs: All important resources SHOULD be identified by a URI." is used, authors are effectively forced to invent ad hoc versioning systems (plural) in order to do URI bookkeeping (both A and A' to be preserved). And the term "MAY" in 1.1.2 in [1] seems like dodging the real issue. Clearly both of the individual advertisements (A and A' in the case 2 above) are important since they might be legally binding etc. And in this case, the difference between a resource and its representation is also pretty thin. ... And you are indeed right, sometimes I do get confused with the terms like "thing", "object in the networked information system", "resource", "representation", "metadata about the representation", and "relationship between things". Well, here are the definitions (of course, all of them are from WDs): From [1] (Web-arch): (a) Objects in the networked information system called resources are identified by Uniform Resource Identifiers (URIs). (b) A representation is data that represents or describes the state of a resource. It consists of: [...] Electronic data expressed in one or more formats [...and] Metadata about the representation, such as the Internet Media Type [...] From [2] (RDF Semantics): (c) The [RDF] semantics treats all RDF names [i.e. URI references or a typed literals] as expressions which denote. The things denoted are called 'resources', following [RFC 2396], but no assumptions are made here about the nature of resources; 'resource' is treated here as synonymous with 'entity', i.e. as a generic term for anything in the universe of discourse. And finally, from [3] (RDF Concepts): (d) The assertion of an RDF triple says that some relationship, indicated by the predicate, holds between the things denoted by subject and object of the triple. ...in other words you can't e.g. use RDF to describe the representations (of resources) since by (d) RDF asserts relationships between things, which by (c) are resources, and by (a) and (b), resources and representations are different (at least by your interpretation). Or then representations indeed are (conceptually) resources, at least in certain context ...to be considered as resources of certain type. I don't want to see all the specs rewritten but yes: I am a bit confused. Cheers, --Ossi [1] http://www.w3.org/TR/webarch/ [2] http://www.w3.org/TR/2003/WD-rdf-mt-20030905/ [3] http://www.w3.org/TR/2003/WD-rdf-concepts-20030905/ -- Ossi Nykänen Tel +358 3 3115 3544 Tampere University of Technology Fax +358 3 3115 3549 DMI / W3C Finnish Office Email ossi@w3.org P.O. Box 553, FIN-33101 Tampere, Finland Web www.w3c.tut.fi
Received on Thursday, 18 September 2003 05:34:09 UTC