$form:tables.field_name
If a form field has at least one value, such a construction returns a table (object of class table) with single column field, containing all field values. It is used for getting multiple field values.
Important notice: before performing operations with a table, you should first check if it exists.
Example
Choose what you like doing in your free time:
<form method="POST">
<p><input type=checkbox name=hobby value="wsurf">windsurfing</p>
<p><input type=checkbox name=hobby value="tv">watching TV</p>
<p><input type=checkbox name=hobby value="books">reading books</p>
<p><input type=submit value="OK"></p>
</form>
$hobby[$form:tables.hobby]
^if($hobby){
Your hobbies are:<br />
^hobby.menu{
$hobby.field
}[<br />] }{
None selected}
The example will output either selected variants or a message informing that nothing has been selected.