Rule-based production system adapted for complex procedures flow

摘要

In a production system in which a plurality of production rules are partitioned into a plurality of clusters for processing to effect cluster control, control expression elements, each describing an instruction for specifying a cluster to be invoked next for execution or an instruction for other flow control, are arranged in the order of execution to provide a control expression part separate from the clusters for processing. An instruction for a return to the control expression part is described in an action part of an appropriate production rule in a cluster, in place of the cluster specifying instruction, so that sequential invocation of clusters can be performed following the instructions described in the control expression part, thereby making it unnecessary to give a description for specifying the name of a cluster to be invoked next for execution in the action part of each production rule.