public boolean isToWrite(){
  Iterator<VariableValue> i=variables.iterator();
  while (i.hasNext()) {
    VariableValue v=i.next();
    if (v.isToWrite()) {
      return true;
    }
  }
  return false;
}

public boolean isToWrite ( ) { Iterator < VariableValue > i = variables . iterator ( ) ; while ( i . hasNext ( ) ) { VariableValue v = i . next ( ) ; if ( v . isToWrite ( ) ) { return true ; } } return false ; }
this variable needs to be written if any of it ' s subsidiary variables needs to be written .
