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run code in 300+ PHP versions simultaneously
<?php $arr = array(1, 2, 3, 4); echo key($arr), "=>", current($arr), "\r\n"; foreach ($arr as $key => &$row) { echo key($arr), "=>", current($arr), "\r\n"; }
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.1, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
0=>1 0=>1 0=>1 0=>1 0=>1
Output for 5.2.2 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.37, 5.6.0 - 5.6.28
0=>1 1=>2 2=>3 3=>4 =>
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/FsPsO on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/FsPsO on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/FsPsO on line 5
Process exited with code 255.
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236.81 ms | 401 KiB | 366 Q