[Om3] CDSignatures/@cd, CDSignatures/@type: how to resolve?

[James Davenport]

On Fri, 9 May 2008, Christoph LANGE wrote:

> Dear James, dear David,
>
>   let me reply to all of your mails at once, in reverse chronological
> order:
>
> On Friday 09 May 2008 12:27:24 David Carlisle wrote:
> > James
> >   Sorry - poor wording on my part. What I meant to say is "what is
> >   meant by
> >   'the standard arith1'?". As I see it, in the absence of an EXPLICIT
> >   CDbase, the application is meant to know, either inherently OR by
> >   going to www.openmath.org, the semantics of the OMS.
> >
> > yes, agreed.
>
> That sounds perfectly reasonable to me. But then we should mention in
> the specification that, if no cdbase is declared in a document, and an
> application does not have its own notion of a CDBase (as e.g. a mathematical
> database might have), http://www.openmath.org/cd must be supported as a
> fallback,  what David called "default-default".
Um - I am very unhappy here: I guess with the whole idea of an
'application-default'. If I write <OMS name="plus" cd="arith1"/> then I DO
mean the standard one, and I DON'T want some application thinking it knows
better. <OMS name="plus" cd="arith1"/> does NOT mean 'anythning you wnat
to call plus'.
>
> Sure, I didn't mean that every system must be able to access the web.
But I
> meant that if some system S references arith1#plus without giving a
CDBase we
> do not know what "arith1" is, whether it is the same CD as
> http://www.openmath.org/cd/arith1.ocd, or whether it is just something
that
> happens to have the same name within S but contains completely different
> definitions. That's also what RDF uses URLs for: not always for actually
> making a connection to some web server and retrieving data, but mostly
just
> for giving things (here: symbols) unambiguous names.
This is my disagreement: I believe that if one sees arith1#plus it DOES
mean the standard one.
>
> So any OpenMath-aware application, be it web-aware or not, should still
be
> aware of the fact that the full, unambiguous name of the "plus" operator
as it
> is officially defined in the openmath.org CDs is
> (cdbase="http://www.openmath.org/cd", cd="arith1", name="plus"), or
> http://www.openmath.org/cd/arith1.ocd, if the application chooses to use
> URLs internally -- that's what I meant to say. Just that we make sure that
> different systems that have their own local representation of CDs are
> actually talking about the same thing when they say "arith1#plus".
As I see it, this would be a significant change.
James