Re: language-tagged literal datatypes

On 08/22/2011 07:55 PM, Richard Cyganiak wrote:
> On 22 Aug 2011, at 17:59, Pierre-Antoine Champin wrote:
>>> Terminology question. What's the “lexical form” of a language-tagged string?
>>>
>>> a) it's a pair of string and language tag
>>> b) it's just the string; the language tag is not considered part of the lexical form
>>> c) it doesn't have one, only typed literals have a lexical form
>>>
>>> My preference would be b), because it seems nicely consistent with the use of the term for typed literals.
>>
>> well, the notion of "lexical form" only makes sense in the context of a
>> datatype, and in relation with a "value".
> 
> Why are you saying that? In RDF 2004, plain literals have a lexical form, despite not having a datatype [1].

oops, my bad...
from that perspective, I concur that my proposal 2c may sound a bit
strange...
but then I sympathize with Pat: I also find strange that a
language-tagged string would have a lexical form and a value, but that
the mapping between the two would not be a L2V mapping... :-/

Then, I don't know which one is the more cumbersome: 2b, a single
magical datatype that maps lexical forms to values without any L2V
mapping, or 3a, an infinite collection of anonymous datatypes with their
own L2V mappings (which are *not* the identity mapping, as they map
"chat" to ("chat", "fr") or ("chat", "en") respectively). In fact, I see
both as two interpretations of the same trick.

So I guess we are converging :-)

  pa

> And a typed literal still has a lexical form even if its datatype IRI doesn't actually name a datatype.
> 
>> In your proposal,
>> rdf:LangString is not a real datatype, and there is no L2V mapping, so
>> at this stage, speaking of the "lexical form" of the language-tagged
>> string seems pointless to me...
>>
>> I'd rather swallow it all and consider that there is no lexical form,
> 
> That would be yet another terminology change from RDF 2004, and I don't see the benefit of that change.
> 
> Quoting from [1]:
> 
> [[
> Plain literals have a lexical form and optionally a language tag […].
> ]]
> 
> This reinforces my preference for b) above. The lexical form of "foo"@en in RDF 1.1 should still be the same as the lexical form of "foo"@en in RDF 2004.
> 
>> (which, in a sense, is already the case for xsd:string as L2V is the
>> identity mapping).
> 
> Not really. Lexical form and value are identical. That doesn't mean it has no lexical form.
> 
>> Note that, if you really want language-tagged strings to have a lexical
>> value (that does not embed the language tag), you might be interested in
>> my proposal 3a from another sub-thread...
> 
> I don't much like 3 nor 3a. There's lots of mechanics there that just complicate the spec and don't actually *do* anything except mapping A to A, and still it misses the original goal of making DATATYPE("foo"@en) in SPARQL a datatype. Your 2c proposal is simpler and better.
> 
> Best,
> Richard
> 
> [1] http://www.w3.org/TR/rdf-concepts/#section-Graph-Literal
>>
>>  pa
>>
>>>
>>> Best,
>>> Richard
>>
>>
>

Received on Monday, 22 August 2011 19:56:58 UTC