Re: XML Schema WG comments on RDF documents

At 2003-03-14 13:00, pat hayes wrote:

>Thanks for your comments on the RDF semantics document.
>
>I will adopt your editorial suggestions, correct typos, and will try to 
>remove uses of terminology with any potential philosophical penumbra from 
>the technical prose in the document.
>
>I have one clarification question concerning your comment on datatypes:
>
>3.2. Types as lexical mappings (schema-related)
>
>       A datatype is an entity characterized by a set of character strings
>       called lexical forms and a mapping from that set to a set of
>       values.
>
>     We have a couple of reservations concerning this characterization.
>...
>      * The statement describes (with the exception of the problem just
>         noted) simple datatypes, but not the class of complex datatypes
>         which can be defined by XML Schema, nor all the types (or
>         type-like constructs) definable in various other schema languages
>         for XML.
>
>I have followed other authors in this characterization, and am somewhat 
>surprised to discover that it is incomplete or inadequate. Can you 
>suggest, or point me to a source for, a definition which does cover the 
>more general case, or which clarifies what is wrong with this 
>characterization? We are supposed to have a datatyping framework which can 
>handle all the built-in XML Schema datatypes.
>
>Thanks for any help you can give.

Thank you for your note. You are quite right: the term 'datatype' is used
in our spec, as in yours, solely in a sense extensionally equivalent
to 'simple type'.  The WG member who drafted our comments has what turned
out to be an isolated minority view of the desirable usage, and the comment
slipped by when the WG reviewed the draft comments without anyone noticing
the problem.

The WG has discussed the issue and confirmed that we do not wish to treat
'datatype' as a synonym for 'type' or as covering both simple types and
complex types.  So we withdraw the comment, with thanks to you for drawing
the problem to our attention.

-C. M. Sperberg-McQueen
  on behalf of the XML Schema Working Group

Received on Saturday, 26 April 2003 08:05:14 UTC