3v4l.org

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<?php $foo = ['a' => 1]; $bar = ['a' => 2]; $baz = ['a' => 3]; var_dump($foo + $bar + $baz); var_dump(array_merge($foo, $bar, $baz));
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(1) { ["a"]=> int(1) } array(1) { ["a"]=> int(3) }

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87.48 ms | 402 KiB | 89 Q