unless($list_info{subscribed_message} ne "" 
       || exists $list_info{subscribed_message}) {
    $list_info{subscribed_message} = $subscribed_message
}

##</code><code>##

if ($list_info{subscribed_message} eq "") {
  $list_info{subscribed_message} = $subscribed_message;
}

##</code><code>##

  sub set_if_not_set_already {
    $_[0] = $_[1] if $_[0] eq ""; 
  }

  set_if_not_set_already($list_info{subscribed_message},
                         $subscribed_message);

##</code><code>##

  sub initialize_list_info {
    $list_info{$_[0]} = $_[1]
        if list_info{$_[0]} eq ""; 
  }

  initialize_list_info('subscribed_message', $subscribed_message);