Re: Datatyping differences

On Mon, 2002-01-28 at 04:53, Patrick Stickler wrote:
> On 2002-01-25 19:22, "ext Dan Connolly" <connolly@w3.org> wrote:
> 
> 
> > What's necessarily
> > the case is that in S, "30" denotes the same thing in all
> > interpretaions, but in TDL it doesn't.
> 
> But how do you know?

Because the specification says so.

> If you don't define the datatype,
> or if your knowledge migrates out of the circle of your
> control?

I don't know how to make sense of that.

> What if I need "30" to mean something else? 

I doubt you really need "30" to mean something else.
Zillions of perl and tcl programmers, for example,
do just fine with just one kind of literal.

I expect you just need to talk about something closely
related to "30", such as the integer whose decimal
(or octal or ...) numeral is "30". You can do that with S.

> What if it is
> supposed to be a monthDay?> How about a human age in years?
> What if it is a magnitude of kilograms?

All handled by S, to my satisfaction. I have working
calendar applications, stuff that does mathmatical
calculations, etc., all using S (S-B, in particular).
See http://www.w3.org/2000/01/sw/ .

> And how could one assign some other interpretation either
> in S or TDL if "30" always denotes the same thing?

One doesn't. If one wants to refer to something other
than the two character string '3' followed by '0',
one uses a different expression than "30".


> I think that your argument has nothing to do with any
> limitation of TDL. I think you will encounter the
> same problems with S as well if you leave datatyping
> knowledge implicit in your application and yet expect
> your data values to be portable to other application
> spaces with the same interpretation.

After several months of implementation experience with S,
I have not run into any problems with S.

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/

Received on Monday, 28 January 2002 08:04:14 UTC