3v4l.org

run code in 300+ PHP versions simultaneously
<?php $headers = "Content-Type: foo/bar\r\n\r\nHost: foo.com\r\n keese\r\nBalls: toast"; print_r(preg_split('/[\r\n]+(?=\S)/', trim($headers), -1, PREG_SPLIT_NO_EMPTY));
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 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, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Array ( [0] => Content-Type: foo/bar [1] => Host: foo.com keese [2] => Balls: toast )

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280.64 ms | 405 KiB | 456 Q