pre(ProgIn,ProgOut) :-
	transform(ProgIn,[],ProgOut).

transform([],Preds,PredCalls) :-
	sort(Preds,UniquePreds),
	makepredcalls(UniquePreds,PredCalls).
transform([(Head :- Body)|RestProgIn],Preds,[NewClause|RestProgOut]) :-
	functor(Head,Name,Arity),
	NewPreds = [Name/Arity | Preds],
	NewClause = (my_pred(Head) :- Body),
	transform(RestProgIn,NewPreds,RestProgOut).

makepredcalls([],[]).
makepredcalls([Name/Arity|R],[(Head :- my_pred(Head))|S]) :-
        functor(Head,Name,Arity),
	makepredcalls(R,S).