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run code in 200+ php & hhvm versions
<?php $a = []; $a[1] = 1; foreach ($a as $k => &$v) { var_dump($v); if ($k == 1) $a[4] = 4; if ($k == 4) $a[2] = 2; }
Output for 7.3.0 - 7.3.4
int(1) int(4)
Output for hhvm-3.10.1 - 3.22.0, 7.0.0 - 7.2.17
int(1) int(4) int(2)
Output for 5.4.0 - 5.6.40
int(1)
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/OAKNO on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/OAKNO on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/OAKNO on line 2
Process exited with code 255.