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Re: reference needed - w3.org versioned documents

From: ashok malhotra <ashok.malhotra@oracle.com>
Date: Thu, 03 Apr 2008 15:35:02 -0700
Message-ID: <47F55B96.4010802@oracle.com>
To: noah_mendelsohn@us.ibm.com
CC: ashok.malhotra@oracle.co, "www-tag@w3.org" <www-tag@w3.org>

Right!  So, we agree that resources can have multiple representations.
If the resource were a horse, you may have a picture of the horse, a 
text description of the horse, etc.
It would be useful to provide a method to find all representations (or 
representation types) of a resource.
Then, some form of (extended) content negotiation could be used to get 
at a particular representation.
Ashok

noah_mendelsohn@us.ibm.com wrote:

>Ashok Malhotra writes:
>
>  
>
>>Are you saying that every non-information resource (thing) has 
>>a single representation?
>>My guess would be several representations.
>>    
>>
>
>No, but I'm noting that generic resources tend to have multiple 
>representations at a given point in time.  For example, the same press 
>release might be available in Greek, French, Chinese, and Japanese.  While 
>I suppose you could try to make the case that it's a rapidly varying 
>resource that changes it's stripes momentarily according the request it 
>receives, I find it easier to consider such a resource as having a state 
>that's the union of it's various natural language translations.  Like that 
>non-information resource, it has many representations, and each one is 
>only a partial view into the entire collection (of course, the generic 
>resource is different in that all the translations are in some sense of 
>some common, underlying abstract document -- to me it's more natural to 
>consider them as a collection, but I understand that others prefer to view 
>the translations as just being like different character encodings, 
>something close to uninteresting plumbing that's needed to make the 
>abstract resource readable by one audience or another.)
>
>Noah
>
>--------------------------------------
>Noah Mendelsohn 
>IBM Corporation
>One Rogers Street
>Cambridge, MA 02142
>1-617-693-4036
>--------------------------------------
>
>
>
>
>
>
>
>
>ashok malhotra <ashok.malhotra@oracle.com>
>Sent by: www-tag-request@w3.org
>04/03/2008 05:46 PM
>Please respond to ashok.malhotra
> 
>        To:     "www-tag@w3.org" <www-tag@w3.org>
>        cc:     (bcc: Noah Mendelsohn/Cambridge/IBM)
>        Subject:        Re: reference needed - w3.org versioned documents
>
>
>
>Hi Noah:
>You said ...
>
>If the resource is a non-information resource then the "representation" 
>(and I understand some would prefer a different term for this case) is 
>necessarily more partial and indirect.  E.g., if I am the resource, the 
>representation might be a picture of me, etc.
>
>Are you saying that every non-information resource (thing) has a single 
>representation?
>My guess would be several representations.
>
>At a minimum there would be the representation and some metadata.  But 
>perhaps
>you don't consider metadata as a representation.
>
>Ashok
>
>
>noah_mendelsohn@us.ibm.com wrote:
>
>  
>
>>Joanthan Rees writes:
>>
>>
>>
>>    
>>
>>>Just the opposite. I'm saying the URI "owner" can and should make 
>>>useful statements about the named resource, but generally doesn't, 
>>>and without these useful statements *I* can't make useful statements 
>>>about what's named because I don't know what's named. I can do as 
>>>many GETs as I like, and I still won't know anything. The W3C's 
>>>statements about its TR URIs qualify as useful statements, but for 
>>>the undated URI I don't think they go far enough to let the the URI 
>>>be a good citizen of the semantic web.
>>>
>>>
>>>      
>>>
>>Let's accept what you say above as true.  In that case do you believe 
>>there is there significant value in sticking to the TAG's position on 
>>httpRange14?  You're making the case that even with the existing 
>>restriction that status code 200 is only for "information resources", a 
>>typical Semantic Web application will still pretty much be depending for 
>>success on the URI owner publishing further information about the 
>>resource.  If that's the case, then why the fuss about 200?  If the owner 
>>    
>>
>
>  
>
>>has to publish more information anyway, then why overload 200?  Why not 
>>rely on that additional information to disambiguate things like info vs. 
>>non-info resources.  In particular, why don't we allow 200 for pretty 
>>    
>>
>much 
>  
>
>>any resource, with the understanding that: 
>>
>>* If the resource is represented using only one media type, and if the 
>>state of the resource is time invariant, then the representation you get 
>>with 200 should be pretty much the whole state of the resource.
>>
>>* If the resource is time varying but otherwise as above, then the 
>>representation should be of its "current" state.
>>
>>* If the resource is generic, for example, a press release available in 
>>French, Greek, English and Chinese, then the representation will 
>>    
>>
>typically 
>  
>
>>be partial (as I prefer to view it), in the sense that it is giving you 
>>only one of the known translations.
>>
>>* If the resource is a non-information resource then the "representation" 
>>    
>>
>
>  
>
>>(and I understand some would prefer a different term for this case) is 
>>necessarily more partial and indirect.  E.g., if I am the resource, the 
>>representation might be a picture of me, etc.
>>
>>You would, of course, not be able to tell which case you were dealing 
>>    
>>
>with 
>  
>
>>unless the URI owner published additional information.  Is there then 
>>confusion in case 4 about statements made about "me" vs. statements made 
>>about the "picture of me"?  Well, you've already said that if the 
>>    
>>
>resource 
>  
>
>>itself were the picture, we wouldn't know that it was unless the URI 
>>    
>>
>owner 
>  
>
>>published additional information.  That being the case, why don't use 
>>    
>>
>that 
>  
>
>>same answer here:  the owner of the URI should publish information saying 
>>    
>>
>
>  
>
>>"this resource is a picture (and therefore, BTW, an information 
>>    
>>
>resource)" 
>  
>
>>or "this resource is a person, and the representations you're getting are 
>>    
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>
>  
>
>>in general pictures of the person".
>>
>>Now, if the statement you made above is in fact not true, then I can see 
>>why the httpRange decision has value.  Then it might be the case that by 
>>merely publishing with 200 the resource owner has given you the 
>>information necessary for it to usefully participate in the Semantic Web, 
>>    
>>
>
>  
>
>>and that's valuable.  Since you've pretty much asserted that's not the 
>>case, then is there still value in the 200 rule?  Thank you.
>>
>>Noah
>>
>>--------------------------------------
>>Noah Mendelsohn 
>>IBM Corporation
>>One Rogers Street
>>Cambridge, MA 02142
>>1-617-693-4036
>>--------------------------------------
>>
>>
>>
>>
>>
>>
>>
>>    
>>
>
>
>  
>


-- 
All the best, Ashok
Received on Thursday, 3 April 2008 22:36:39 GMT

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