Say I have a database that looks something like this:
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'].
Is it possible to reference facts from production rules to eliminate the duplication I have here.