3v4l.org

run code in 300+ PHP versions simultaneously
<?php $source = [ <<<'EOD' \n EOD , <<<'EOD' \\n EOD , <<<'EOD' \\\n EOD ]; var_dump(preg_replace('~\\\\.(*SKIP)(?<=n)~', "\n", $source));
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array(3) { [0]=> string(1) " " [1]=> string(3) "\\n" [2]=> string(3) "\\ " }
preferences:
133.98 ms | 407 KiB | 5 Q