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run code in 200+ php & hhvm versions
Bugs & Features
<?php return preg_replace_callback( '/(?<=(&lt;|<)$s(&gt;|>))(.*)(?=(&lt;|<)\/$s(&gt;|>))/i', function($matches){var_dump($matches);die;}, '<tag>stuff</tag>' );
Output for 7.0.0 - 7.2.0
Warning: preg_replace_callback(): Compilation failed: lookbehind assertion is not fixed length at offset 22 in /in/UDulN on line 6
Output for 5.3.22 - 5.6.28
Warning: preg_replace_callback(): Compilation failed: lookbehind assertion is not fixed length at offset 22 in /in/UDulN on line 7