problema con substr

[whisher]

function truncate($string, $max = 200, $rep = '..') { 
    if (strlen($string) <= ($max + strlen($rep))) { 
        return $string; 
    } 
    $leave = $max - strlen ($rep); 
    return substr_replace($string, $rep, $leave); 
} 

Presa da php.net non trovo + il link