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Re: Proposal: #rdfms-identity-anon-resources

From: Dan Connolly <connolly@w3.org>
Date: Wed, 18 Jul 2001 13:21:43 -0500
Message-ID: <3B55D3B7.810E98E2@w3.org>
To: Aaron Swartz <me@aaronsw.com>
CC: Graham Klyne <Graham.Klyne@Baltimore.com>, RDF core WG <w3c-rdfcore-wg@w3.org>
Aaron Swartz wrote:
> 
> On Thursday, July 12, 2001, at 02:02  AM, Dan Connolly wrote:
> 
> > from aaron:
> >
> > |I think all parsers should spit out
> > |equivalent genids for the same document -- the spec should
> > |mandate the genid to use.
> >
> > I'm pretty sure there is no algorithm for coming up
> > with genids that works; i.e. there's no algorithm
> > for sorting the triples in a graph: you can't treat a graph
> > as if the edges didn't (sometimes) cross.
> 
> This isn't necessary -- you only need to say something like
> they're numbered based on the location of the XML element that
> defined them, or that they random UUIDs or something.

Random uuids won't meet the requirement I understand you're after,
which is that different parsers would compute the same URI for
anonymous nodes given the same RDF input.

Random uuids are, effectively, skolem constants, which see
other thread about whether reducing existentially quantified
variables to skolem constants is OK or not. (my position: not).

I've noodled on the approach of naming things based on their
XML element position, and I've convinced myself that won't
work either. I don't have a proof that there's no such algorithm,
but I'm not likely to spend more time thinking about it until
somebody makes a concrete suggestion (i.e. running code)
of an algorithm that works.

I'm pretty sure that, at a minimum, it requires the sort
of tricks involved in putting a signature inside a signed
document.



-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
office: tel:+1-913-491-0501
mobile: mailto:connolly+pager@w3.org?subject=pls%20call%20+1-...
Received on Wednesday, 18 July 2001 14:22:14 EDT

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