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<?php $test = array( 'abc' => 123, 'def' => 456, 'test' => array( 123 => 'hip', 'hop' => null ) ); foreach ($test as $old => &$arr) { if (is_array($arr)) { unset($test[$old]); foreach ($arr as $new => $v) { $test[$old.$new] = $v; } } } var_dump($test);
Output for 7.0.0 - 7.0.20, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(4) { ["abc"]=> int(123) ["def"]=> int(456) ["test123"]=> string(3) "hip" ["testhop"]=> &NULL }
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28
array(4) { ["abc"]=> int(123) ["def"]=> int(456) ["test123"]=> string(3) "hip" ["testhop"]=> NULL }
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/T8722 on line 12
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/T8722 on line 12
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/T8722 on line 12
Process exited with code 255.

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