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run code in 200+ php & hhvm versions
<?php $x = '#'; var_dump(substr( $x, 1 ));# "yoman"
Output for hhvm-3.15.4 - 3.22.0, 7.0.0 - 7.3.5
string(0) ""
Output for 4.3.0 - 5.0.5, 5.1.1 - 5.6.40, hhvm-3.10.1 - 3.13.2
bool(false)
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/Dk0Rg on line 4
Process exited with code 255.