3v4l.org

run code in 300+ PHP versions simultaneously
<?php class Foo implements Iterator { public function current(): Foo { return $this; } public function key(): Foo { return $this; } public function next(): void {} public function rewind(): void {} public function valid(): bool { return true; } } foreach ( new Foo as $key => $value ) { var_dump($key, $value); break; }

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