Re: Objects and Relations

On 24 fév, 10:24, "Alfredo Novoa" <alfred..._at_gmail.com> wrote:
> On 23 feb, 14:20, "Cimode" <cim..._at_hotmail.com> wrote:
>
> > >From what I understand in OO:
>
> > OO -------> RM
> > Class <--> Relation Structure, Relation Variable --> (value holder)
>
> Class <--> Type = Domain
>
> > Class Instantiation <--> Relation Value
>
> Class Instantiation = Object <--> Scalar Value or Scalar Variable
>
> These are rough equivalences of course because the OO terms don't have
> serious definitions.
>
> Regards
If you define class by domain then what is the RM equivalent for relation?
In RM, a domain is *not* the same* as a type or a relation. (
domain = set of *possible* values for which a relation draws *possibly* values
relation = ((struture+name) + constraints --> rules and structure to restrict validity of values drawn from domain and that constitute the body of relation)
typing = making a domain from a relation body and name (therefore only *existing* values for a specific relation). )
I think you are right. I have not found so far any conceptual tools in OO that allow for instance the distinction between *possible*, *permissible* and *existing* values. Received on Sat Feb 24 2007 - 13:43:11 CET