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Re: subtypes of xsd:string

From: Ivan Herman <ivan@w3.org>
Date: Thu, 26 May 2011 12:32:57 +0200
Cc: <david.wood@talis.com>, <richard@cyganiak.de>, <jeremy@topquadrant.com>, <public-rdf-wg@w3.org>
Message-Id: <19DA7FC6-12FA-4B14-B0E6-0E22E75358D0@w3.org>
To: Peter Frederick Patel-Schneider <pfps@research.bell-labs.com>

On May 26, 2011, at 03:21 , Peter Frederick Patel-Schneider wrote:
[skip]
> 
>> - add a subtype of xsd:string for language tagged strings;
>> 
>>  "foo"@en -> "foo"^^xsd:LanguageTaggedString@en or some such.
> 
> Here is where this breaks down, just like the previous proposals like
> it.
> 

I may be wrong in what David wants, so I try to interpret what he says which is

"foo"@en -> "foo"^^rdf:language-tag/en

or something like that. 

We always fall back to the same two choices, actually: either we define a generic URI scheme to define a load of datatype URI-s for language tags, or we go down the rdf:LanguageTaggedString route.

I must admit I begin to more in favour of the datatype per language tag idea than I was before, provided that we do not even try to enforce any kind of extra semantics for them. Ie, we do _not_ claim to know whether

rdf:language-tag/lang-extras

is a subclass of

rdf:language-tag/lang

Smart and language aware implementations may add their own extra knowledge in terms of extra axioms (and let the generic inference mechanism work). We can only say that all these classes are subclasses of xsd:string.

I would still like to see what the implementation costs of all this would be for Jena, Sesame, RDFLib, etc; something that we might explicitly ask the community to comment upon.

Ivan


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Received on Thursday, 26 May 2011 10:30:55 GMT

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