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run code in 200+ php & hhvm versions
Bugs & Features
<?php var_dump(substr("a", 1));
Output for hhvm-3.15.4 - 3.17.3, 7.0.0 - 7.2.0
string(0) ""
Output for 4.3.0 - 5.6.30, hhvm-3.10.1 - 3.13.2
bool(false)