Re: Getting to closure on the remaining issues - issue-92

On 24 Jan 2013, Eric Prud'hommeaux wrote as shown in the archive
http://lists.w3.org/Archives/Public/public-ldp-wg/2014Jan/0121.html
> On 24 Jan 2014, at 18:38, Henry Story <henry.story@bblfish.net> wrote:
> 
>> On 24 Jan 2014, at 18:14, Alexandre Bertails <bertails@w3.org> wrote:
>> 
>>>>>>> 
>>>>>>> In plain English: ldp:Container happens to be a class that can be used
>>>>>>> to denote the Container interaction model when used with
>>>>>>> rel=profile. What's wrong in that sentence?
>>>>>> 
>>>>>> What does it denote when it is not used with rel=profile?
>>>>> 
>>>>> Then the behavior is not defined. It's ok because we're only
>>>>> interested in defining what it means when we use it with rel=profile,
>>>>> or when you use it as a class.
>>>> 
>>>> A URI refers to one thing. This is not a question of behaviour. That
>>>> is how URIs are defined.
>>>> 
>>>> [[
>>>>   A Uniform Resource Identifier (URI) provides a simple and extensible
>>>>   means for identifying a resource.
>>>> ]]
>>> 
>>> I gave you the one declarative and universal meaning for
>>> ldp:Container: it denotes the LDPC interaction model when used with
>>> rel=profile, you're on your own for other rels.
>>> 
>>> Does this introduce any contradiction with anything else?
>> 
>> yes, there is no such thing as "denoting something when used with ..."
>> Have you got a definition of that somewhere?
>> 
>> Some further supporting evidence from RDF Semantics:
>> 
>> [[ http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#urisandlit
>> 
>> This document does not take any position on the way that URI references may be composed from other expressions, e.g. from relative URIs or QNames; the semantics simply assumes that such lexical issues have been resolved in some way that is globally coherent, so that a single URI reference can be taken to have the same meaning wherever it occurs.
>> ]]
>> 
>> So imagine you have some other relation that is like profile but narrower, say an ldp:profile
>> then ldp:Container would have to still refer to the same thing in the relation below:
>> 
>>  <> ldp:profile ldp:Container .
>> 
>> which if we translate it using your grue like definition would come to
>> 
>>  <> is related by the ldp:profile relation to the thing denoting the ldp interaction if related by rel=profile, 
>>     but you're out of luck for other rels.
>> 
>> so here it would be 
>> 
>>  <> related by ldp:profile to we know not what.
>> 
>> What if someone then wants to write a vocabulary that describes interaction models?
>> Say they want to say of an interaction model that it supports POST and that this creates
>> new resources in some way,.... 
>> 
>>  ldp:Container interaction:methodSupported "GET", "PUT", "POST", "PATCH" .
>> 
>> following the above reasoning we have no idea what ldp:Container is referring to above.
>> 
>> Clearly this would go against all the semantic web reasoning layers that have been agreed
>> to in various groups at the W3C. 
>> 
>>  I am surprised you even think of presenting this as an argument!
>> You have just helped me  thump another stake in the heart 
>> of this rel=profile time consuming vampire .
> 
> And I am surprised that you think it's reasonable to use the same identifier for a graph representing an LDP container AND the protocol for interacting with it.


You mean that <http://example/> in say { <http://example> a ldp:Container . } would refer to a Graph? 

Only if the Graph can be a temporal thing that can change over time, which is not the
strict definition of Graph in the RDF specs.

The representation returned by <http://example/> is a Graph, but you must not
confuse the representation with the resource. The resource is something that
has an interaction model, and that can change over time, whilst keeping its
identity of course  :-) . The representation returned is something that can 
be interpreted in terms of a graph, and whose content describes a set of 
possibilities. In the case of { <> a ldp:Container }, the graph returned
as the representation describes the resource as being one of the objects which
can be interacted with according to the ldp spec.

This is just basic REST: Representation of State Transfer. The representation is
a represntation of a _Resource_ referred to by a URI.

Henry


>> 
>>   Henry
>> 
>> 
>> Social Web Architect
>> http://bblfish.net/
>> 
> 
>

Received on Friday, 24 January 2014 18:37:31 UTC