3v4l.org

run code in 300+ PHP versions simultaneously
<?php function foo() { yield 1; yield 2; yield 3; yield 4; } var_dump(foo() instanceof Traversable); $fooG = foo(); array_walk($fooG, function ($foo) { var_dump($foo); }); iterator_apply($fooG, function ($foo) { var_dump($foo); });

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