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<?php $x = [ 'a' => 3, 'b' => 6, ]; $y = [ 'c' => 1, 'd' => 3, 'a' => 1, ]; var_dump($x + $y); var_dump($y + $x);
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.12 - 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(4) { ["a"]=> int(3) ["b"]=> int(6) ["c"]=> int(1) ["d"]=> int(3) } array(4) { ["c"]=> int(1) ["d"]=> int(3) ["a"]=> int(1) ["b"]=> int(6) }
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/Eg5hQ on line 3
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/Eg5hQ on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/Eg5hQ on line 3
Process exited with code 255.

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