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Re: Fw: Possible problem in collection definition

From: Albert Lunde <atlunde@panix.com>
Date: Sun, 19 Feb 2006 17:27:24 -0500
To: webdav <w3c-dist-auth@w3.org>
Message-ID: <20060219222724.GA13517@panix.com>

On Sun, Feb 19, 2006 at 03:01:37PM -0500, Jason Crawford wrote:
> I'm suggesting that all equivalent segments refer to the same (single) 
> mapping.  When you act on any of those segments, you're acting on the same 
> mapping.  We should also say that PROPFIND should list all bindings of the 
> collection at least once and if a binding is listed more than once, the 
> server is allowed to list a different equivalent segment for each. 
> 
> There is a second alternative that I'd consider consistent.    We can say 
> that every equivalent segment also has a mapping to the same resource. 
> (IOW's the number of equivalent segments is equal to the number of 
> "mappings".)  We'd say if you change one mapping, the server has to change 
> the mapping at all equiv segments.  As for the  PROPFIND statement above, 
> we'd have to invent some term (for a set of equivalent segments and 
> mappings)  to express the first part of that in this context.  (That's why 
> I prefer the previous paragraph's definition.) 
> 
> Those two alternatives seem to be the only options to me.  Saying that the 
> number of "mappings" can be somewhere between 1 and the number 
> of equivalent segments does not seem consistent ot me.  If we say that, we 
> have to then distinguish between (listed) mappings... and 
> [some-new-"mapping"-like-term] for the unlisted and clarify acts on each 
> and resulting behaviors of each.  This is over and above the additional 
> term we'd need to express the second approach.  

It seems like a possible way to formalize this would be
the mathematical notion of an equivalance relation and 
equivalance classes.

If you assume a server MAY apply some notion of canonical path
equivalence (which defines an equivalence relation), then it would 
map equivalence classes of paths to resources, instead of mapping 
paths to resources.

(This is probably orthogonal to webdav's multiple bindings.)

-- 
    Albert Lunde  albert-lunde@northwestern.edu
                  atlunde@panix.com  (new address for personal mail)
                  albert-lunde@nwu.edu (old address)
Received on Sunday, 19 February 2006 22:27:26 GMT

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