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Steps and Effects

A plan step Step represents an action. It may have enabling preconditions. It has at least one effect Eff. It is the instantiation of an operator.

A plan step may be a decision-step Decide. A decision-step has enabling preconditions of the form (know-if Cond) for a condition Cond. Decide also has a set of decision-rules.

An effect Eff represents some results of an action. It is attached to a step Step, representing that action. It may have secondary preconditions. It has at least one postcondition Cond, a condition that becomes true as the result of executing Step when the secondary preconditions hold.

Louise Pryor <>;
Last modified: Wed May 1 11:27:54 1996