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run code in 200+ php & hhvm versions
Bugs & Features
<?php $var = [ 'a' => 'a', 'b' => 'b', ]; foreach ($var as $value) { } var_dump(key($var));
Output for 7.0.0 - 7.2.0
string(1) "a"
Output for 5.5.0 - 5.6.28
NULL