[sc34wg3] Look Ma! No Properties!

[Jan Algermissen]

Robert,

I had posted two other questions about your proposal. Maybe you missed
them. Here they are again:

Thanks.

Jan


Robert Barta wrote:
> 
> On Thu, Jul 15, 2004 at 08:08:11PM -0400, Patrick Durusau wrote:
> 
> > Ok, the \tau model has no properties.
> 
> The \tau model is based on assertions only. Properties are seen as
> only a special form of an assertion, yes.

Uhm...I don't get it. How are properties seen as a special form of
assertion?

> Just to make an example to avoid a too abstract discussion: Lets
> assume we model students with their names, their shoesize and their
> student ID (SID). In the 'assembler-like' tau model we would only have
> assertions:
> 
>  { < name-haver:     jack-learner >, < name     : "Jack Learner" > },
>  { < shoesize-haver: jack-learner >, < shoesize : 1234 > }
>  { < sid-haver:      jack-learner >, < SID      : 12345678 > }

I guess I am missing the step how you group together the assertions that
have members (r1,p1),(r2,p1),(r3,p1) with p1 E N     (not I !!)
and how this enables the forall semantics on p1, allowing you to
view name,shoesize and SID as properties.

> forall [ $s1
>          SID: $sid1 ]
>    => not exists [ $s2
>                    SID: $sid1 ]

If I got that right....



-- 
Jan Algermissen                           http://www.topicmapping.com
Consultant & Programmer	                  http://www.gooseworks.org