- From: Dominique Hazaël-Massieux <dom@w3.org>
- Date: Thu, 19 Aug 2004 13:13:04 +0200
- To: Nick Kew <nick@webthing.com>
- Cc: www-validator@w3.org
- Message-Id: <1092913983.3180.37.camel@stratustier>
Le mar 17/08/2004 à 16:02, Nick Kew a écrit : > > identifier; depending on the URI scheme, the said identifier may or may > > not be dereferenceable; in some URI scheme, there is an authoritative > > representation of the URI that can be obtained following a well-defined > > protocol. For instance, http: URIs can be obtained through the HTTP > > protocol, which also defines a caching mechanism. > > But the HTTP protocol is perfectly clear that content may be dynamic. > As soon as you dereference a URI, you lose the guarantee of uniqueness > that is fundamental to the vocabulary/RDF usage. I'm not sure of what you mean by uniqueness, here; I see 2 different topics: - the fact that the representation you get when dereferencing a URI may vary; I don't see how this impact the identification part of a URI - the fact that one URI may be used to identify 2 different things, againts which there is indeed no guarantee but social pressure, but this is not limited to HTTP URIs nor do I see the link to dynamic content. > > Hmm... We're drifting a long way off the initial discussion :) To reply > > shortly, Annotea is indeed better used on stable resources rather than > > changing ones - but stable resources doesn't mean static; also, I think > > Annotea now deals well with content negotiation, using the > > Content-Location header as it should. But I guess this should be rather > > discussed on www-annotations :) > > Content-Location doesn't make the dereferenced content unique or > invariant. Indeed; but it doesn't need to be; I referred to Content-Location since you were saying that Annotea was failing with negotiated content, and dealing with the Content-Location header addresses this point, as far as I can tell. I don't see what makes you think that annotea fails on dynamic content; more precisely, I'm not sure what you see as a failure of the annotation protocol, given its scope; it's pretty clear to me that annotating a resource that changes a lot is likely to break, but that is not a failure of a protocol, but rather a probably bad choice of a target for annotations (the same way that linking to the W3C home page for a specific news published in the past week is a bad idea since the news are rotating on this home page). > The bottom line is confusion. Annotea is fundamentally broken because > it assumes invariance (and XML well-formedness - but that's another story) > of dereferenced content. XML Well-formedness is not a requirement of annotea, since it works on HTML 4.0; note that even if it was, that doesn't make it broken, but restricted to a specific domain - you may question whether this restriction is appropriate for your usage, but I don't think that makes the whole protocol broken. As to invariance, I still fail to see what you mean. > I submit that this is entirely relevant to the > current discussion, because it demonstrates what's wrong with W3C's usage > of URI. So be it, then :) > Not that either usage of URI is intrinsically wrong, or even problematic. > Not even that both usages can't in principle work together. > But that *in practice*, they are often confused in the W3C's work, > because each usage has its own 'community', and not everyone appreciates > the difference. The fact that it takes time for a technology to be well-used and well-understood is very true, and the validators developers are better placed than anyone to know this; I don't think refusing a technology only because it takes time to explain/understand it is a good thing to do. > There are ivory towers - particularly in semweb-land - > constructed on this confusion. And too much historical baggage to > fix it as W3C would like. "Too much historical baggage to fix it as W3C would like"... that could make a good epitaph for the W3C Validator ;o) Dom -- Dominique Hazaël-Massieux - http://www.w3.org/People/Dom/ W3C/ERCIM mailto:dom@w3.org
Received on Thursday, 19 August 2004 11:13:10 UTC