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Re: circular relationships ok?

From: Volker Hetzer <volker.hetzer_at_ieee.org>
Date: Thu, 02 Mar 2006 17:46:26 +0100
Message-ID: <du77h2$1cq$1@nntp.fujitsu-siemens.com>


Alexandr Savinov schrieb:
> A model with cycles is not a concept-oriented model (theoretically). It
> is a strong constraint but it is part of the definition. Then the
> question is if it is useful or not. For any model there are examples
> which are non-trivial and very difficult to implement. Loops and cycles
> can be always avoided by introducing a common subconcept. If A and B
> mutual reference each other then we introduce a common subconcept C:
>
> A B
> \ /
> C

Ok, here goes:

    Net<-------\

     |         |
     V         |
    Constraint*|
     |         |
     V         |
     Token*    |
     /   \     |
     |    -----/
     V

Constant

(* denotes "zero or more")
("Token" refers to either a constant or a Net, not both.)

How would you do it?
Maybe I'm blind but I simply don't see it. My problem is that the relations are directed. A Nrt doesn't refer to constraints and tokens, a net refers to constraints and the token optionally refers to another net. Even if I add a Token/Net table, I still have the circle.

Lots of Greetings!
Volker Received on Thu Mar 02 2006 - 10:46:26 CST

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