$arr[] -= 1; var_dump($arr); class T { public $str; public $int; function __construct() { $this->str = ''; $this->int = 0; } function bongo($a, $b) { $this->str .= $a; $this->int += $b; } } $t = new T(); $t->bongo("eine", 1); $t->bongo(":zwei", 2); var_dump($t); $a = array(5); $zero = 0; $a[$zero] += 1; var_dump($a); $x = 40; $arr = array(); $arr[0] =& $x; $arr[0] += 4; var_dump($x); print "Test end\n";