1--TEST--
2Test usort() function : usage variations - Anonymous comparison function
3--FILE--
4<?php
5/* Prototype  : bool usort(array $array_arg, string $cmp_function)
6 * Description: Sort an array by values using a user-defined comparison function
7 * Source code: ext/standard/array.c
8 */
9
10/*
11 * Pass an anonymous comparison function as $cmp_function argument to test behaviour()
12 */
13
14echo "*** Testing usort() : usage variation ***\n";
15
16$cmp_function = function($value1, $value2) {
17    if ($value1 == $value2) { return 0; }
18    else if ($value1 > $value2) { return 1; }
19    else { return -1; }
20};
21
22$array_arg = array(0 => 100, 1 => 3, 2 => -70, 3 => 24, 4 => 90);
23
24echo "\n-- Anonymous 'cmp_function' with parameters passed by value --\n";
25var_dump( usort($array_arg, $cmp_function) );
26var_dump($array_arg);
27
28$array_arg = array("b" => "Banana", "m" => "Mango", "a" => "Apple", "p" => "Pineapple");
29
30$cmp_function = function(&$value1, &$value2) {
31    if ($value1 == $value2) { return 0; }
32    else if ($value1 > $value2) { return 1; }
33    else { return -1; }
34};
35
36echo "\n-- Anonymous 'cmp_function' with parameters passed by reference --\n";
37var_dump( usort($array_arg, $cmp_function) );
38var_dump($array_arg);
39?>
40===DONE===
41--EXPECTF--
42*** Testing usort() : usage variation ***
43
44-- Anonymous 'cmp_function' with parameters passed by value --
45bool(true)
46array(5) {
47  [0]=>
48  int(-70)
49  [1]=>
50  int(3)
51  [2]=>
52  int(24)
53  [3]=>
54  int(90)
55  [4]=>
56  int(100)
57}
58
59-- Anonymous 'cmp_function' with parameters passed by reference --
60bool(true)
61array(4) {
62  [0]=>
63  string(5) "Apple"
64  [1]=>
65  string(6) "Banana"
66  [2]=>
67  string(5) "Mango"
68  [3]=>
69  string(9) "Pineapple"
70}
71===DONE===
72