--TEST-- Test array_keys() function (variation - 4) --FILE-- TRUE, FALSE => FALSE, 1 => 1, 0 => 0, -1 => -1, "1" => "1", "0" => "0", "-1" => "-1", NULL, array(), "php" => "php", "" => "" ); $values = array(TRUE, FALSE, 1, 0, -1, "1", "0", "-1", NULL, array(), "php", ""); foreach ($values as $value){ var_dump(array_keys($types_arr, $value, TRUE)); } echo "Done\n"; ?> --EXPECT-- *** Testing array_keys() on all the types other than arrays *** array(0) { } array(0) { } array(0) { } array(0) { } array(0) { } array(1) { [0]=> int(1) } array(1) { [0]=> int(0) } array(1) { [0]=> int(-1) } array(1) { [0]=> int(2) } array(1) { [0]=> int(3) } array(1) { [0]=> string(3) "php" } array(1) { [0]=> string(0) "" } Done