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run code in 200+ php & hhvm versions
Bugs & Features
<?php $array=["a"=>b,"c"=>"d"]; echo json_encode($array);
Output for 7.2.0
Warning: Use of undefined constant b - assumed 'b' (this will throw an Error in a future version of PHP) in /in/07CeV on line 3 {"a":"b","c":"d"}
Output for 5.4.0 - 7.1.10
Notice: Use of undefined constant b - assumed 'b' in /in/07CeV on line 3 {"a":"b","c":"d"}