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run code in 150+ php & hhvm versions
Bugs & Features
<?php $x=new stdClass(); $y=1002; $x->$y = ''; var_dump(key(array(1002=>'')), key((array)$x));
Output for 5.1.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
int(1002) string(4) "1002"
Output for 4.3.2 - 4.4.0, 4.4.2 - 5.0.5
Fatal error: Only variables can be passed by reference in /in/YREaX on line 7
Process exited with code 255.
Output for 4.4.1
int(1002) int(1002)
Output for 4.3.0 - 4.3.1
Fatal error: Only variables can be passed by reference in /in/YREaX on line 7