PHP: references in foreach

revision 3b058f8be51a3ddb3053b460083e63221b1f3274

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

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