--TEST-- Test array_diff_key() function : usage variation - Passing integer indexed array --FILE-- '-07', 0xA => '0xA'); $input_arrays = array( 'decimal indexed' => array(10 => '10', '-17' => '-17'), 'octal indexed' => array(-011 => '-011', 012 => '012'), 'hexa indexed' => array(0x12 => '0x12', -0x7 => '-0x7', ), ); // loop through each element of the array for arr1 foreach($input_arrays as $key =>$value) { echo "\n--$key--\n"; var_dump( array_diff_key($input_array, $value) ); var_dump( array_diff_key($value, $input_array) ); } ?> ===DONE=== --EXPECT-- *** Testing array_diff_key() : usage variation *** --decimal indexed-- array(1) { [-7]=> string(3) "-07" } array(1) { [-17]=> string(3) "-17" } --octal indexed-- array(1) { [-7]=> string(3) "-07" } array(1) { [-9]=> string(4) "-011" } --hexa indexed-- array(1) { [10]=> string(3) "0xA" } array(1) { [18]=> string(4) "0x12" } ===DONE===