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run code in 150+ php & hhvm versions
Bugs & Features
<?php var_dump(substr('a', 1)); var_dump(substr('a', 1, null)); var_dump(substr('a', 1, 0)); var_dump(substr('a', 1, 1)); var_dump(substr('', 0)); var_dump(substr('', 0, null)); var_dump(substr('', 0, 0)); var_dump(substr('', 0, 1)); var_dump(substr('', 1)); var_dump(substr('', 1, null)); var_dump(substr('', 1, 0)); var_dump(substr('', 1, 1));
Output for 7.0.0 - 7.1.0
string(0) "" string(0) "" string(0) "" string(0) "" string(0) "" string(0) "" string(0) "" string(0) "" bool(false) bool(false) bool(false) bool(false)
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0
bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false) bool(false)