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<?php $array1 = array( "a" => "first", "b" => "second", "c" => "something", "red" ); $array2 = array( "a" => "first", "b" => "something", "letsc" ); print_r(array_fill_keys($array1, $array2));
Output for 7.1.25 - 7.3.5
Array ( [first] => Array ( [a] => first [b] => something [0] => letsc ) [second] => Array ( [a] => first [b] => something [0] => letsc ) [something] => Array ( [a] => first [b] => something [0] => letsc ) [red] => Array ( [a] => first [b] => something [0] => letsc ) )