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run code in 150+ php & hhvm versions
Bugs & Features
<?php $x = "bug"; var_dump(isset($x[-1]));
Output for 5.0.0 - 5.0.2, 7.1.0
bool(true)
Output for 4.3.3 - 4.4.9, 5.0.3 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.0.14
bool(false)
Output for 4.3.0 - 4.3.2
Notice: Uninitialized string offset: -1 in /in/pebln on line 5 bool(false)