3v4l.org

run code in 300+ PHP versions simultaneously
<?php function chain(...$iters) { foreach ($iters as $iter) { yield from $iter; } } $gen = (function() { yield 1; yield 2; yield 3; })(); $repeatedTwice = chain($gen, $gen); foreach ($repeatedTwice as $v) var_dump($v);

preferences:
40.61 ms | 402 KiB | 5 Q