public Pair addElseIf(ExprBoolean condition,Statement body,Position start,Position end){
  Pair pair;
  ifs.add(pair=new Pair(condition,body,start,end));
  body.setParent(this);
  return pair;
}

public Pair addElseIf ( ExprBoolean condition , Statement body , Position start , Position end ) { Pair pair ; ifs . add ( pair = new Pair ( condition , body , start , end ) ) ; body . setParent ( this ) ; return pair ; }
adds a else statement
