1--TEST--
2Test usort() function : usage variations - Anonymous comparison function
3--FILE--
4<?php
5/*
6 * Pass an anonymous comparison function as $cmp_function argument to test behaviour()
7 */
8
9echo "*** Testing usort() : usage variation ***\n";
10
11$cmp_function = function($value1, $value2) {
12    if ($value1 == $value2) { return 0; }
13    else if ($value1 > $value2) { return 1; }
14    else { return -1; }
15};
16
17$array_arg = array(0 => 100, 1 => 3, 2 => -70, 3 => 24, 4 => 90);
18
19echo "\n-- Anonymous 'cmp_function' with parameters passed by value --\n";
20var_dump( usort($array_arg, $cmp_function) );
21var_dump($array_arg);
22
23$array_arg = array("b" => "Banana", "m" => "Mango", "a" => "Apple", "p" => "Pineapple");
24
25$cmp_function = function(&$value1, &$value2) {
26    if ($value1 == $value2) { return 0; }
27    else if ($value1 > $value2) { return 1; }
28    else { return -1; }
29};
30
31echo "\n-- Anonymous 'cmp_function' with parameters passed by reference --\n";
32var_dump( usort($array_arg, $cmp_function) );
33var_dump($array_arg);
34?>
35--EXPECTF--
36*** Testing usort() : usage variation ***
37
38-- Anonymous 'cmp_function' with parameters passed by value --
39bool(true)
40array(5) {
41  [0]=>
42  int(-70)
43  [1]=>
44  int(3)
45  [2]=>
46  int(24)
47  [3]=>
48  int(90)
49  [4]=>
50  int(100)
51}
52
53-- Anonymous 'cmp_function' with parameters passed by reference --
54
55Warning: {closure}(): Argument #1 ($value1) must be passed by reference, value given in %s on line %d
56
57Warning: {closure}(): Argument #2 ($value2) must be passed by reference, value given in %s on line %d
58
59Warning: {closure}(): Argument #1 ($value1) must be passed by reference, value given in %s on line %d
60
61Warning: {closure}(): Argument #2 ($value2) must be passed by reference, value given in %s on line %d
62
63Warning: {closure}(): Argument #1 ($value1) must be passed by reference, value given in %s on line %d
64
65Warning: {closure}(): Argument #2 ($value2) must be passed by reference, value given in %s on line %d
66
67Warning: {closure}(): Argument #1 ($value1) must be passed by reference, value given in %s on line %d
68
69Warning: {closure}(): Argument #2 ($value2) must be passed by reference, value given in %s on line %d
70bool(true)
71array(4) {
72  [0]=>
73  string(5) "Apple"
74  [1]=>
75  string(6) "Banana"
76  [2]=>
77  string(5) "Mango"
78  [3]=>
79  string(9) "Pineapple"
80}
81