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Re: "tdb" and "duri" URI schemes...

From: Nathan <nathan@webr3.org>
Date: Wed, 03 Nov 2010 14:42:03 +0000
Message-ID: <4CD174BB.7090709@webr3.org>
To: Larry Masinter <masinter@adobe.com>
CC: Jonathan Rees <jar@creativecommons.org>, "www-tag@w3.org" <www-tag@w3.org>
Hi Larry,

Larry Masinter wrote:
>> Dated uri does seem like a very useful addition to the web, however it's 
>> semantics could be simplified as such:
> 
> I'm not sure how you suggest the semantics be simplified. I'm 
> in favor of simplicity but...
> 
>> Regardless, I strongly feel that "Thing Described By" would be best 
>> dropped, it's confusing at the least,
> 
> I agree that it might be confusing, but I personally see a great
> difference between me and my web page, and that when I say
> "http://larry.masinter.net", I have to mean one or the other
> (or perhaps both), but that they aren't the same. I haven't come
> across anyone who was confused about what 'tdb' was trying to do.

Likewise I too see a great difference between me and my web page, no 
confusion there, and make that distinction using different names/URIs, 
for example:

   <http://webr3.org/> my homepage(~ish}
   <http://webr3.org/nathan> a document primarily about me
   <http://webr3.org/nathan#me> me

(assuming base to be http://webr3.org/), here's a simple set of 
statements in n3/turtle:

  </nathan> a :Document ; :primarilyAbout </nathan#me> .
  </nathan#me> a :Person ; :made </nathan> .

or in english:

  </nathan> is a document primarily about </nathan#me>.
  </nathan#me> is a person who made the </nathan>.

thus..

>> can you imagine how many will ask 
>> "what's the difference between a duri and a tdb?"
> 
> I haven't seen anyone asking this question... are you?

yes... see below

>> and it's a valid 
>> question even now, "when should I use a tdb instead of a duri? and are 
>> the consequences of using the wrong one?" - 
> 
> Those are good questions, but the answers depend on context,
> and I can't find a context where there is an actual question
> about it....

I would like to "say" the two statements mentioned above using duri/tdb 
to say that:

   the document identified by </nathan> in 2010 was primarily about 
</nathan#me> in 2010.
   in 2010 </nathan#me> identified a person, who made the document 
</nathan> (in 2010).

so in an n3/turtle version of the above, should I be using tdb's or 
duri's and in which combination? what are the consequences of using the 
wrong ones?

>> and in reply to the reply to 
>> that question, if there are no consequences then why make a distinction? 
>> and if there are consequences then are you prepared to introduce that in 
>> to the web?
> 
> There are consequences.
> I don't think that providing a way of distinguishing me from my web
> page "introduces" the consequences.

You'll see above that I've already distinguished me from the document 
primarily about me, using http scheme URIs, the two things have 
different names, so this is more about the distinctions between tdb and 
duri scheme uris, like the following:

   <tdb:2010:http://webr3.org/nathan>
   <duri:2010:http://webr3.org/nathan>
   <tdb:2010:http://webr3.org/nathan#me>
   <duri:2010:http://webr3.org/nathan#me>

So, to bring this back to the main point, I suggest you only need duri: 
and that the description & meaning is clear:

    The meaning of a 'duri' URI is "the resource that was identified by
    the <encoded-URI> (after hex decoding) at the date(time) given".

Thus,

<duri:2010:http://webr3.org/nathan>
    the resource that was identified by <http://webr3.org/nathan> at 2010

<duri:2010:http://webr3.org/nathan#me>
    the resource that was identified by <http://webr3.org/nathan#me> at 2010

Which allows me to again write:

  </nathan> a :Document ; :primarilyAbout </nathan#me> .
  </nathan#me> a :Person ; :made </nathan> .

But this time the base is <duri:2010:http://webr3.org/> rather than 
<http://webr3.org/>.

All nice and simple when tdb: is removed the equation.

Best,

Nathan
Received on Wednesday, 3 November 2010 14:43:04 GMT

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