%
% the Yale shooting problem -- no 'dead' fluent 
%

% to see what happens, use the command 
% lparse -c n=1 yale.lp | smodels 
% add o(load, 0) to the program and rerun
% to see the problem 

% define fluents and actions 

fluent(alive).
fluent(loaded).

action(shoot).
action(load).

% define time line 

time(0..n).

% initial state 

h(alive, 0).
h(neg(loaded), 0). 

% action effects 

% shooting causes neg(alive) only if 
% 

h(neg(alive), T+1):-
    time(T), o(shoot, T), h(loaded, T).

h(neg(loaded), T+1):-
    time(T), o(shoot, T), h(loaded, T).

% loading causes loaded 

h(loaded, T+1):-
    time(T), o(load, T).

% hiding fluent and action 

hide fluent(F).
hide action(A).

% hiding time 

hide time(T).