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Re: RDF-ISSUE-89 (at-prefix): Should Turtle allow SPARQL's PREFIX like @prefix? [RDF Turtle]

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Fri, 11 May 2012 12:14:18 +0100
Message-ID: <4FACF48A.8040801@epimorphics.com>
To: public-rdf-wg@w3.org


On 11/05/12 11:48, Steve Harris wrote:
> On 2012-05-10, at 22:59, Sandro Hawke wrote:
>
>> On Thu, 2012-05-10 at 19:53 +0100, Richard Cyganiak wrote:
>>> Sandro,
>>>
>>> I'm sitting on the fence regarding @prefix, and don't like the barewords idea.
>>>
>>>> But when I imagine introducing new people to Turtle, as I expect to be
>>>> doing for many years once it becomes a Recommendation, I can't think of
>>>> any way to justify that odd character.
>>>
>>> It's not just the initial @, also the trailing period. Turtle has:
>>>
>>>    @prefix foaf:<http://xmlns.com/foaf/0.1/>.
>>>
>>> SPARQL has:
>>>
>>>    PREFIX foaf:<http://xmlns.com/foaf/0.1/>
>>
>> Indeed, I forgot about that, and Eric reminded me earlier today.  Yes.
>>
>>> The period is actually a bigger problem than the @, IMO.
>>>
>>> On the other hand, someone who has to learn a completely new language
>>
>> My sense is that people moving between Turtle and SPARQL wont think of
>> it as a completely new language.   Particularly if they learned SPARQL
>> first, then Turtle is effectively just a subset of Turtle.   But in
>> either case, I think it will often seem like one language, where SPARQL
>> just involves using a bunch of extra features of the language.
>>
>>> won't be bothered greatly by one extra character here or there, IMO. It's rare that newbies point out inconsistencies in the grammar of a new language that they learn.
>>
>> I suppose that depends a lot on the context.   In a SemWeb context,
>> they're often learning so much other stuff --- well, things like
>> httpRange-14 draw a lot more heat than @prefix, it's true.
>>
>>> The same argument that you make for @prefix can be made for @base. Do you suggest changing @base too?
>>
>> Yes, absolutely.
>>
>> I might phrase it now as:
>>
>> PROPOSED: Make the @-sign and period optional on 'prefix' and 'base' in
>> Turtle
>
> That is an option - but it may be less confusing to allow exactly either:
>
> @prefix foo:<http://foo.example/>  .   [N3 style]
>     or
> PREFIX foo:<http://foo.example/>       [SPARQL style]
>
> You can't put a . between PREFIXes in SPARQL, and I don't think we should add that as an option, it wouldn't fit with the rest of the language.

@base vs BASE

>
> I'm kind of ambivalent about this, it's probably a good idea, but I've never heard a complaint about it.

I am more concerned by:
[[
with PREFIX preferred and used in all the examples
]]

>
> - Steve
>

	Andy
Received on Friday, 11 May 2012 11:14:53 GMT

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