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run code in 150+ php & hhvm versions
Bugs & Features
<?php $string 'Test comment subject<\h1>'; $pattern = 'Test comment subject(?<!<\h1>)'; preg_match($string, $pattern, $matches); print_r($matches);
Output for 5.4.0 - 5.4.29
Parse error: syntax error, unexpected ''Test comment subject<\h1>'' (T_CONSTANT_ENCAPSED_STRING) in /in/YQIjp on line 2
Process exited with code 255.
Output for 5.3.0 - 5.3.28
Parse error: syntax error, unexpected T_CONSTANT_ENCAPSED_STRING in /in/YQIjp on line 2
Process exited with code 255.