3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array( 'a' => null, 'b' => false, 'c' => true, 'd' => "", 'e' => 0, 'f' => 1, 'g' => "a", ); foreach($a as $key => $row) { echo $key . "\n"; var_dump(isset($row)); var_dump(!empty($row)); echo "\n"; }

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33.26 ms | 402 KiB | 5 Q