3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array(1,2,3,4,5,6,7,8,9,10); $key = 2; foreach (new CallbackFilterIterator(new ArrayIterator($a), function($v, $k) use ($key) { static $good = false; $good |= $k === $key; return $good; }) as $v) { echo $v; }
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 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
345678910
Output for 5.3.0 - 5.3.29
Fatal error: Class 'CallbackFilterIterator' not found in /in/5Iksl on line 4
Process exited with code 255.
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/5Iksl on line 4
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/5Iksl on line 4
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/5Iksl on line 4
Process exited with code 255.

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