--TEST-- Test array_intersect_key() function : usage variation - Passing boolean indexed array --FILE-- '0', 1 => '1' , -10 => '-10'); $boolean_indx_array = array(true => 'boolt', false => 'boolf', TRUE => 'boolT', FALSE => 'boolF'); echo "\n-- Testing array_intersect_key() function with boolean indexed array --\n"; var_dump( array_intersect_key($input_array, $boolean_indx_array) ); var_dump( array_intersect_key($boolean_indx_array,$input_array ) ); ?> ===DONE=== --EXPECTF-- *** Testing array_intersect_key() : usage variation *** -- Testing array_intersect_key() function with boolean indexed array -- array(2) { [0]=> string(1) "0" [1]=> string(1) "1" } array(2) { [1]=> string(5) "boolT" [0]=> string(5) "boolF" } ===DONE===