Re: Datalog (DLV) question

andrew_at_acooke.org wrote:
> ...
>
> I want to make sure that every "call" predicate (which
> describes a message being sent) has a first argument which is a
> process. I used:
>
> :- call(P, _, _, _, _), not process(P, _).
>
> as a strong constraint, but this is unsafe. Some example data:
>
>...
>
> How do I express this constraint (I am worried that I have errors in my
> data and want to detect them)?
>
>...

Andrew

Have a look at constraint handling rules:

http://en.wikipedia.org/wiki/Constraint_Handling_Rules

http://www.cs.kuleuven.ac.be/~dtai/projects/CHR/

Regards.

• nef