🚀 go-pugleaf

In article <718322659.0@nwark.FidoNet>, Bert.Edens@f1160.n391.z1.FidoNet.Org (Bert Edens) writes:
>     monster(orc,4).
> where the latter is the number of hit points. What I want to do is add up a
> group of them and get the total hit points for an attack party. For
> example, it might be:
>     monster(orc,4). monster(kobold,5). monster(goblin,8).
> and I want to add them up.

You need a way to represent what is in the attack party.
For argument's sake, let's assume that a hit party is represented by
a list of HowMany*MonsterType pairs, e.g. [2*goblin,3*orc].

attack_party_hit_points(Monsters, HitPoints) :-
	attack_party_hit_point_loop(Monsters, 0, HitPoints).

attack_party_hit_point_loop([], HP, HP).
attack_party_hit_point_loop([K*M|KMs], HP0, HP) :-
	monster(M, H),
	HP1 is HP0 + K*H,
	attack_party_hit_point_loop(KMs, HP1, HP).

The data base is the place for information that doesn't change or changes
very infrequently; terms are the place for information that changes rapidly.