public void genMethods(PrintWriter out, String base, boolean ret)
public void genMethods(PrintWriter out, String base, boolean ret, boolean gen_impl)
  public void genMethods(PrintWriter out, String base, boolean ret)  {    for(int i=0; i<size(); i++) {      ATermAppl appl = ((ATermAppl)elementAt(i));      if (ret)	out.print("  abstract ATerm " + base + "(");      else	out.print("  abstract void " + base + "(");      genFormals(out, appl.getArguments());      out.println(");");    }  }