class PrefixedConsole extends Console {

  public PrefixedConsole(int val){
    myMaxSize = val;
  }

  public String getPrefix() {
    return ">>";
  }

  public void display(String s){
    @pre{s.length() < trg_instance.getMaxSize() - getPrefix().length()}
    super.display(this.getPrefix() + s);
  }

}