1--TEST-- 2Test usort() function : usage variations - referenced variables 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 array of referenced variables as $array_arg to test behaviour 12 */ 13 14echo "*** Testing usort() : usage variation ***\n"; 15 16function cmp_function($value1, $value2) 17{ 18 if($value1 == $value2) { 19 return 0; 20 } 21 else if($value1 > $value2) { 22 return 1; 23 } 24 else { 25 return -1; 26 } 27} 28 29// different variables which are used as elements of $array_arg 30$value1 = -5; 31$value2 = 100; 32$value3 = 0; 33$value4 = &$value1; 34 35// array_args an array containing elements with reference variables 36$array_arg = array( 37 0 => 10, 38 1 => &$value4, 39 2 => &$value2, 40 3 => 200, 41 4 => &$value3, 42); 43 44echo "\n-- Sorting \$array_arg containing different references --\n"; 45var_dump( usort($array_arg, 'cmp_function') ); 46var_dump($array_arg); 47?> 48===DONE=== 49--EXPECT-- 50*** Testing usort() : usage variation *** 51 52-- Sorting $array_arg containing different references -- 53bool(true) 54array(5) { 55 [0]=> 56 &int(-5) 57 [1]=> 58 &int(0) 59 [2]=> 60 int(10) 61 [3]=> 62 &int(100) 63 [4]=> 64 int(200) 65} 66===DONE=== 67