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The deductive control (see Figure 13) may affect the deductive
knowledge of a module by inhibiting rules or deducing instances of the
meta-predicate K. Moreover, instances of any user-defined meta-predicate
can be generated. These meta-rules are responsible for the
implementation of a type of meta-reasoning based on changing the object level
theory in two ways: by reducing it (eliminating some rules), or by changing it
(deducing instances of the meta-predicate K). Next you have a
description of the meta-predicates allowed in the conclusions of this type of
meta-rules. The action to be taken after a meta-rule deduces an instance of
these meta-predicates is explained in Section 5.1.3.
- Inhibit Rules:
- This action inhibits all the rules containing the
fact pathpredid in their premises. Optionally we can introduce a
name of relation relation-id. Then the rules inhibited will then be
those containing in its premises a fact related with pathpredid.
- It inhibits all the rules belonging to the deductive tree of
the fact pathpredid.
- Here users are allowed to conclude any meta-predicate.
Only when the meta-predicate is the predefined K an action consisting on
overwriting a fact value at the object level will be undertaken in the
reflection phase. The remaining instances of user-defined predicates will remain
as part of the meta-level state, and will eventually be used as conditions of
other meta-rules to be fired in this and in posterior activations of the
Thu Oct 23 15:34:13 MET DST 1997