Global function in file auto_prepend.php:

/**
 * Same as ED(), but if first argument is foo then $GLOBALS['debug_foo'] must be set for output
 * @return boolean indicating whether $GLOBALS['debug_foo'] was set
 */
function EDC($var, ...$args)
{
    $GLOBALS['ULTRADEBUGVARS'][$var] = 1;

    if (($result = $GLOBALS["debug_$var"]))
    {
        if ($args)
        {
            it_debug::setup();
            it_debug::echo($args);
        }

        if (!$result || $result === true)       # Compatibility with old map relying on 0|1
            $result = intval($result);
    }

    return $result;
}