Easzars nb_setarg/3

agg_all_(min(X,W), Goal, min(X,W)) :-
  State = state(X,W,LastMin),
  (  call(Goal),
     arg(1, State, M0),
      M is min(M0,X),
      M \== LastMin,
     nb_setarg(1, State, M),
     nb_setarg(2, State, W),
     nb_setarg(3, State, M),
     fail
  ;
     arg(1, State, X),
     arg(2, State, W)
  ).