3v4l.org

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<?php $targetArray = array('a'=>'','b'=>'','c'=>'','d'=>''); $sourceArray = array('a'=>'a','c'=>'c','d'=>'d'); var_export(array_replace($targetArray, $sourceArray)); var_export($sourceArray + $targetArray);
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array ( 'a' => 'a', 'b' => '', 'c' => 'c', 'd' => 'd', )array ( 'a' => 'a', 'c' => 'c', 'd' => 'd', 'b' => '', )

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