[rules-users] Truth maintenance

[Andreas Volz]

Hi,

I have a question concerning the truth maintenance mechanism in Drools:
Is it possible to exclude some preconditions from truth maintenance?

We want to implement a rule flow by using an attribute of a special
fact (ProcessPhaseController.phase).
We have some phases that we want to traverse. In each phase only some
of our rules should be activated.
Therefore all of our rules test for a certain phase; e.g.:

when
    ProcessPhaseController(phase == ProcessPhase.EXEC)
...

When no rule of the current phase is activated, a special rule changes
the phase to the next one and the rules of the next phase are evaluated.

The problem now is that we have some rules with logical inserts. So
each time the phase is changed, all of these inserts are retracted.
To prevent this I would like to exclude the condition
"ProcessPhaseController(phase == ProcessPhase.EXEC)" from truth
maintenance. Is this possible?

Thanks in advance!

Cheers,
Andreas

-- 
Andreas Volz
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