php yield example

<?php

function yield_test() {
$timestart=time();
print "first element retrieved... ";
yield (time()-$timestart);
print "second element retrieved... ";
yield (time()-$timestart);
print "third element retrieved... ";
yield (time()-$timestart);
}


foreach (yield_test() as $v ) {
print $v." seconds passed\n";
sleep(2);
}