%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% At run time, this below predicate will be build
% and used to pass information. 
% 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

solution(Customer, Requirements, 
         Old_sol, New_sol, Difference). 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% instantiated example
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% note that the capability description may be a subset
% of a particular type of board. 

solution(john-1, 
         [total_cost(M), 
          less_than(M, 1000),
          special_req(B, capability, [fast_graphics])
          ], 

          [], 
          []  ). 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% init_solution indicates a minimum solution
% for any requirement, i.e. an io, a disk_controller 
% and processor board must be allocated. 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

init_solution(
          Customer, 
          Requirements, 

          [ instance_of(X, processor), 
            instance_of(Y, disk_controller),
            instance_of(Z, io), 
            allocate(X,  Slot1),
            allocate(Y,  Slot2),
            allocate(Z,  Slot3),
            total_cost(Cost) ], 

          Solution ). 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%