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run code in 200+ php & hhvm versions
Bugs & Features
<?php ${0} = 'ab'; $a = 'a'; $b = 'b'; print ${$a + $b};
Output for 7.1.0 - 7.2.0
Warning: A non-numeric value encountered in /in/iO3Gg on line 8 Warning: A non-numeric value encountered in /in/iO3Gg on line 8 ab
Output for 4.3.0 - 7.0.20
ab