PHP: references in foreach

revision 3efdb850eba698c30a0c913b7499802db8822965

<?php
$a = [1,2];
var_dump($a);
 
foreach ($a as &$val) {}
var_dump($a);
 
$b = [3];
foreach ($b as $val) {}
var_dump($a);
?>

array(2) {
  [0]=>
  int(1)
  [1]=>
  int(2)
}
array(2) {
  [0]=>
  int(1)
  [1]=>
  &int(2)
}
array(2) {
  [0]=>
  int(1)
  [1]=>
  &int(3)
}