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run code in 300+ PHP versions simultaneously
<?php $mtest1 = null; if (!isset($mtest2) ) [ echo 'is not set'; } if ($mtest2 == null) { echo 'is null'; } if (!isset($mtest2) || $mtest2 == null) [ echo 'is not set'; }
Output for 5.4.0 - 5.4.29
Parse error: syntax error, unexpected 'echo' (T_ECHO), expecting ']' in /in/KOc0J on line 5
Process exited with code 255.
Output for 5.3.0 - 5.3.28
Parse error: syntax error, unexpected '[' in /in/KOc0J on line 4
Process exited with code 255.
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