Re: varieties of datatyped tagged literals

On Wed, 2011-09-07 at 19:30 +0100, Andy Seaborne wrote:
> 
> On 07/09/11 17:42, Pierre-Antoine Champin wrote:
> > Following todays's discussion, let me rephrase the rationale of each
> > "family" of solution:
> 
> Thanks. Pat gives teh details; this is good to discuss the general 
> intent of each approach.
> 
> >
> > 1. Don't change anything: literals will have *either* a datatype or a
> > literal.
> >
> > In the following options, we unify literals by ensuring that every
> > literal has a datatype.
> >
> > 2. The language tag is still "outside" the (lexical/value) mechanism of
> > the datatype; the various sub-options differ in how this
> > extra-information is introduced in the system.
> >
> > In the following options, we unify literals even more by making
> > language-tagged literals a special case of datatyped literal.
> >
> > 3. The language tag is attached to the by the datatype.
> >
> > 4. The language tag is attached to the lexical form.
> 
> A RDF 1.0 literal has three parts:
>     (lexical form, language tag, datatype)
> 
> with lang and datatype being optional.
> 
> Options 2, 3 and 4 remove the optionality on datatype.
> 
> Option 2 still has optional language tag; there is a single datatype for 
> lang-tag literals.
> 
> Option 3 removes the lang slot and encodes it into the URI.
> (or requires a dereference).
> 
> Option 4 removes the lang slot and encodes it into the lexcial form.
> 
> For 3 vs 4, if you emphasis datatypes more than lexical forms, you like 
> 3 and conversely, if you emphasis lexical forms, 3 is preferable to 4.
> 
> Options 3 and 4 reduce the dimensionality to 2 by encoding.
> 
> All options make language tags "special" in some way.  Option 2 does it 
> bypassing L2V; options 3 and 4 rely on micro-parsing (further parsing a 
> string).

Very, very nicely put.   I dislike 2 because it doesn't get us down to
two elements.  I prefer 3 over 4 because I think datatype URIs are a
better place to do the encoding than data values -- URIs are already
full of delimiters and parameters understood by different components.
Forcing the data values to also be parsed doesn't feel right, although I
concede it does work.

     -- Sandro


>  Andy
> 
>

Received on Wednesday, 7 September 2011 19:06:35 UTC