\begin{tomcode3}[label=code:strategyPeanoTransform,caption=Exemple d'utilisation de stratégie.]
  %strategy transformationPeano() extends Identity() {
    visit Nat {
      plus(x, zero()) -> { return `x; }
      plus(zero(), x) -> { return `x; }
      one() -> { return `suc(zero()); }
    }
  }
  ...
  public static void main(String[] args) {
    ...
    Nat number = `plus(plus(suc(suc(one())), one()),
                         plus(suc(one()), zero()) );
    Strategy transformStrat = `BottomUp(transformationPeano());
    Nat transformedNumber = transformStrat.visit(number);
    System.out.println(number + " a #\texttt{é}#t#\texttt{é}# transform#\texttt{é}# en " + transformedNumber);
    ...
  }
\end{tomcode3}
