This adds support for: $array1 = ['a' => 1, 'b' => 2]; $array2 = ['b' => 3, 'c' => 4]; $array = [...$array1, ...$array2]; // => ['a' => 1, 'b' => 3, 'c' => 4] RFC: https://wiki.php.net/rfc/array_unpacking_string_keys Closes GH-6584.
RFC: https://wiki.php.net/rfc/spread_operator_for_array Closes GH-3640.