3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $f = function() { $a = yield - 1; }; foreach ($f() as $i) { var_dump($i); }
based on 3gKpc
Output for hhvm-3.15.4, 7.0.0 - 7.3.0rc3
int(-1)
Output for 5.6.0 - 5.6.30
NULL