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run code in 150+ php & hhvm versions
Bugs & Features
<?php preg_match('#/(?<\1>.+)#', '/foo');
Output for 4.3.11 - 7.1.0
Warning: preg_match(): Compilation failed: unrecognized character after (?< at offset 4 in /in/BdLpa on line 3
Output for 4.3.0 - 4.3.10
Warning: Compilation failed: unrecognized character after (?< at offset 4 in /in/BdLpa on line 3