High-level comments on datatyping draft

I think in the current draft a more clear separation between the abstract
syntax and the RDF/XML syntax is needed (the original RDF spec suffered
from exactly this problem). The first figure in Sec. 3.1 illustrates
nicely what datatypes are about in the abstract syntax - they are
first-class citizens in graphs. This point can be made earlier.

I'm also uneasy about nailing down the internal structure of datatype
values as a 4-tuple or the like. I think literals should be opaque wrt RDF
abstract syntax. This makes the data model simple and appealing.
In addition, in implementations literals might be mapped directly to
native types and not have any structure whatsoever. Insisting that they do
would make implementations more complex and less efficient.

It seems that all that business of rdfs:Datatype, value spaces and
lexical spaces could be eliminated. What we care about are the value
spaces, c'est tout.

Finally, I think that global datatyping (Sec. 3.2) is out of scope of the
current document. At this point of time we do not have a mechanism
robust enough to standardize on global datatyping. If we trash it the
document might appear sparse. IMO a simple but beautiful incremental
step is way better than a "lemon".

Sergey

Received on Monday, 26 August 2002 10:34:55 UTC