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Bugs & Features
<?php $a = array(false => 1); var_dump(array_key_exists(false, $a));
based on p4UbO
Output for 4.3.2 - 7.2.0
Warning: array_key_exists(): The first argument should be either a string or an integer in /in/R2sok on line 4 bool(false)
Output for 4.3.0 - 4.3.1
Warning: array_key_exists() [http://www.php.net/function.array-key-exists]: The first argument should be either a string or an integer in /in/R2sok on line 4 bool(false)