是否有可能在生產規則中引用事實？

Question

說我有一個看起來像這樣的數據庫：

regular_player('Xi'). 
regular_player('Doyle'). 

expert_player('Houdini'). 
expert_player('Gandhi'). 

% don't allow expert players to be paired together 
start  --> good_pair. 
good_pair --> (player, expert) ; (expert, player) ; (player, player). 
player  --> ['Xi'] ; ['Doyle']. 
expert  --> ['Houdini'] ; ['Gandhi']. 

是否有可能從生產規則引用的事實，以消除重複我這裏。

Answer 1

您可以消除事實並改用player和expert規則。

或者，限定

player --> [P], { regular_player(P) }. 
expert --> [E], { expert_player(E) }. 

至於其做法是適當的是依賴於應用的。