<?php
/* Script showing that reset() takes its parameter by reference */
if (defined('HHVM_VERSION')) {
exit;
}
// adapted from http://php.net/manual/en/language.references.php#99644
$g_refcount_added = 0;
function refcount($var)
{
ob_start();
debug_zval_dump($var);
$dump = ob_get_clean();
$matches = array();
preg_match('/refcount\(([0-9]+)/', $dump, $matches);
$count = $matches[1];
global $g_refcount_added;
return $count - $g_refcount_added;
}
// configure our refcount function
$array = array('key' => 'value');
$refcount_expected = 1;
$refcount_actual = refcount($array); // 3 in PHP 7.0, 4 in other versions
$g_refcount_added = $refcount_actual - $refcount_expected;
unset($refcount_actual, $refcount_expected, $array);
// end of configure our refcount function
function print_refcounts($label, $orig_rc, $copy_rc = null)
{
if ($copy_rc === null) {
printf("%s : orig %d %s (%s)\n", $label, $orig_rc, " ", 'alone');
} else {
printf("%s : orig %d, copy %d (%s)\n", $label, $orig_rc, $copy_rc, $copy_rc > 1 ? 'sharing' : 'separated');
}
}
$orig = array('foo' => 'bar');
print_refcounts("initially ", refcount($orig));
$copy = $orig;
print_refcounts("after copy", refcount($orig), refcount($copy));
reset($copy); // if the argument is passed by reference, PHP separates $copy and $orig
print_refcounts("after call", refcount($orig), refcount($copy));
preferences:
32.98 ms | 402 KiB | 5 Q