Slot accessing method in object-oriented expert system

摘要

A slot accessing method in an object-oriented expert system, wherein data, which is indicative of necessity or non-necessity of re- computation of a slot value and which is created according to a dynamic dependency between a reference slot and a reference slot, is set in a reference slot of an object having a reference rule. When the re- computation is necessary, a flat "T" indicative of the effect is set, whereas when the re-computation is unnecessary, a flat "NIL" indicative of the effect is set. When the value of a slot of an object having a reference slot as its slot value is changed, it is judged whether or not it is necessary to re- compute the slot value of the corresponding reference slot on the basis of data that is indicative of necessity or non-necessity of re- computation of the slot value and that is set in the corresponding reference slot. If the flag "NIL" is set in the corresponding reference slot, then no re-computation is carried out for the slot value.