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run code in 300+ PHP versions simultaneously
<?php $matches=null; $fortune = 'The rain in Spain<br> -- whoknows'; if (strpos($fortune,"--") !== FALSE) { preg_replace("/^--([ a-zA-Z])+$/m","<p> -- " . ${1} . "</p>",$matches); var_dump($matches); }
Output for 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: Undefined variable $1 in /in/M1QeY on line 5 Deprecated: preg_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /in/M1QeY on line 5 NULL
Output for 8.0.0 - 8.0.30
Warning: Undefined variable $1 in /in/M1QeY on line 5 NULL
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: 1 in /in/M1QeY on line 5 NULL
Output for 7.3.32 - 7.3.33
NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: 1 in /in/M1QeY on line 5 NULL

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