1--TEST-- 2Test array_map() function : usage variations - callback function with different return types 3--FILE-- 4<?php 5/* Prototype : array array_map ( callback $callback , array $arr1 [, array $... ] ) 6 * Description: Applies the callback to the elements of the given arrays 7 * Source code: ext/standard/array.c 8 */ 9 10/* 11 * Test array_map() by passing different callback function returning: 12 * int, string, bool, null values 13 */ 14 15echo "*** Testing array_map() : callback with diff return value ***\n"; 16 17$array1 = array(1, 2, 3); 18$array2 = array(3, 4, 5); 19 20echo "-- with integer return value --\n"; 21function callback_int($a, $b) 22{ 23 return $a + $b; 24} 25var_dump( array_map('callback_int', $array1, $array2)); 26 27echo "-- with string return value --\n"; 28function callback_string($a, $b) 29{ 30 return "$a"."$b"; 31} 32var_dump( array_map('callback_string', $array1, $array2)); 33 34echo "-- with bool return value --\n"; 35function callback_bool($a, $b) 36{ 37 return TRUE; 38} 39var_dump( array_map('callback_bool', $array1, $array2)); 40 41echo "-- with null return value --\n"; 42function callback_null($array1) 43{ 44 return NULL; 45} 46var_dump( array_map('callback_null', $array1)); 47 48echo "-- with no return value --\n"; 49function callback_without_ret($arr1) 50{ 51 echo "callback_without_ret called\n"; 52} 53var_dump( array_map('callback_without_ret', $array1)); 54 55echo "Done"; 56?> 57--EXPECTF-- 58*** Testing array_map() : callback with diff return value *** 59-- with integer return value -- 60array(3) { 61 [0]=> 62 int(4) 63 [1]=> 64 int(6) 65 [2]=> 66 int(8) 67} 68-- with string return value -- 69array(3) { 70 [0]=> 71 string(2) "13" 72 [1]=> 73 string(2) "24" 74 [2]=> 75 string(2) "35" 76} 77-- with bool return value -- 78array(3) { 79 [0]=> 80 bool(true) 81 [1]=> 82 bool(true) 83 [2]=> 84 bool(true) 85} 86-- with null return value -- 87array(3) { 88 [0]=> 89 NULL 90 [1]=> 91 NULL 92 [2]=> 93 NULL 94} 95-- with no return value -- 96callback_without_ret called 97callback_without_ret called 98callback_without_ret called 99array(3) { 100 [0]=> 101 NULL 102 [1]=> 103 NULL 104 [2]=> 105 NULL 106} 107Done 108