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<?php $array = [ 'firstname', 'bob', 'lastname', 'alex', 'foo', ]; var_export( array_reduce( $array, function ($result, $v) { static $k; if ($k === null) { $k = $v; } else { $result[$k] = $v; $k = null; } return $result; }, [] ) );
Output for 8.1.32 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array ( 'firstname' => 'bob', 'lastname' => 'alex', )

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