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<?php $array_x = array(); $array_x['a'] = array(1,2,3,4); $array_x['b'] = array(2,3,4,5); foreach ($array_x as $k => &$v) { foreach ($v as $x) { $x = $x * 2; } } var_dump($array_x);
Output for 5.2.1 - 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(2) { ["a"]=> array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) } ["b"]=> &array(4) { [0]=> int(2) [1]=> int(3) [2]=> int(4) [3]=> int(5) } }
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0
array(2) { ["a"]=> &array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) } ["b"]=> &array(4) { [0]=> int(2) [1]=> int(3) [2]=> int(4) [3]=> int(5) } }
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/tVUhn on line 7
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/tVUhn on line 7
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/tVUhn on line 7
Process exited with code 255.

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