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<?php $a = [ 'a' => ['first' => 1], 'b' => ['first' => 2], 'c' => ['first' => 3], ]; foreach ($a as &$i) { $i['second'] = $i['first']; } foreach ($a as $i) {} var_dump($a);
Output for 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(3) { ["a"]=> array(2) { ["first"]=> int(1) ["second"]=> int(1) } ["b"]=> array(2) { ["first"]=> int(2) ["second"]=> int(2) } ["c"]=> &array(2) { ["first"]=> int(2) ["second"]=> int(2) } }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/nnIeN 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 '[' in /in/nnIeN on line 4
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/nnIeN on line 4
Process exited with code 255.

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