--TEST-- Test array_filter() function : basic functionality --FILE-- <?php /* Prototype : array array_filter(array $input [, callback $callback]) * Description: Filters elements from the array via the callback. * Source code: ext/standard/array.c */ echo "*** Testing array_filter() : basic functionality ***\n"; // Initialise all required variables $input = array(1, 2, 3, 0, -1); // 0 will be considered as FALSE and removed in default callback /* Callback function * Prototype : bool even(array $input) * Parameters : $input - input array each element of which will be checked in function even() * Return type : boolean - true if element is even and false otherwise * Description : This function takes array as parameter and checks for each element of array. * It returns true if the element is even number else returns false */ function even($input) { return ($input % 2 == 0); } // with all possible arguments var_dump( array_filter($input,"even") ); // with default arguments var_dump( array_filter($input) ); echo "Done" ?> --EXPECTF-- *** Testing array_filter() : basic functionality *** array(2) { [1]=> int(2) [3]=> int(0) } array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [4]=> int(-1) } Done