Example:

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      :-table dfs/2.
      :-eager_consume dfs/2.
      dfs(State,Plan):-
          is_final_state(State),!,
          Plan=[].
      dfs(State,[Move|Plan]):-
          select_move(State,Move),
          update(State,State1),
          dfs(State1,Plan).

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This program implements the depth-first search algorithm over a state space. It terminates once a plan is found. Without the eager_consume declaration, however, the program would explore all the state space and would never stop if there are infinite number of plans.