php closure example

#!/usr/bin/env php
<?php

function counter ($n) {
    error_log("starting counter at $n");
    return function () use (&$n) {
        return ++$n;
    };
}

$c1 = counter(20);
$c2 = counter(77);

$i = 10;
while ($i-- > 0) {
    echo $c1() . "\t" . $c2() . "\n";
}

?>