It's a macro called UserList that lists all usernames stored in the database. It's invoked just like any other macro: [[UserList]]
Update: small fix to the SQL query to not return the empty username.
In lib/defaults.php, locate the ViewMacroEngine array and add the entry: 'UserList' => 'view_macro_userlist'. The code should look like the following:
$ViewMacroEngine = array(
//...
'UserList' => 'view_macro_userlist'
);
Copy and paste the following code into parse/macros.php:
function view_macro_userlist() {
global $pagestore, $PgTbl;
$first = true;
$query = $pagestore->dbh->query("SELECT DISTINCT(`username`) FROM $PgTbl WHERE `username` != '' ORDER BY `username`");
while (($result = $pagestore->dbh->result($query))) {
if ($first) {
$first = false;
$text = html_ul_start() . "\n";
}
$text .= html_li_start() . html_ref($result[0], $result[0]) . html_li_end();
}
if ($text) {
$text .= html_ul_end() . "\n";
}
return ($text);
}
If there's enough demand for it, I can modify the code to include CurlyOptions that customize the output (unless someone else would like to try it). --PaulBernays