1--TEST-- 2Test array_diff_key() function : usage variation - Passing boolean indexed array 3--FILE-- 4<?php 5echo "*** Testing array_diff_key() : usage variation ***\n"; 6 7// Initialise function arguments not being substituted (if any) 8$input_array = array(0 => '0', 1 => '1', -10 => '-10', 'true' => 1, 'false' => 0); 9$boolean_indx_array = array(true => 'boolt', false => 'boolf', TRUE => 'boolT', FALSE => 'boolF'); 10 11echo "\n-- Testing array_diff_key() function with boolean indexed array --\n"; 12// loop through each element of the array for arr1 13var_dump( array_diff_key($input_array, $boolean_indx_array) ); 14var_dump( array_diff_key($boolean_indx_array, $input_array) ); 15?> 16--EXPECT-- 17*** Testing array_diff_key() : usage variation *** 18 19-- Testing array_diff_key() function with boolean indexed array -- 20array(3) { 21 [-10]=> 22 string(3) "-10" 23 ["true"]=> 24 int(1) 25 ["false"]=> 26 int(0) 27} 28array(0) { 29} 30