1--TEST-- 2Test ?? operator 3--FILE-- 4<?php 5 6$var = 7; 7$var2 = NULL; 8 9$obj = new StdClass; 10$obj->boo = 7; 11 12$arr = [ 13 2 => 7, 14 "foo" => "bar", 15 "foobar" => NULL, 16 "qux" => $obj, 17 "bing" => [ 18 "bang" 19 ] 20]; 21 22function foobar() { 23 echo "called\n"; 24 return ['a']; 25} 26 27var_dump($nonexistent_variable ?? 3); 28echo PHP_EOL; 29var_dump($var ?? 3); 30var_dump($var2 ?? 3); 31echo PHP_EOL; 32var_dump($obj->boo ?? 3); 33var_dump($obj->bing ?? 3); 34var_dump($arr["qux"]->boo ?? 3); 35var_dump($arr["qux"]->bing ?? 3); 36echo PHP_EOL; 37var_dump($arr[2] ?? 3); 38var_dump($arr["foo"] ?? 3); 39var_dump($arr["foobar"] ?? 3); 40var_dump($arr["qux"] ?? 3); 41var_dump($arr["bing"][0] ?? 3); 42var_dump($arr["bing"][1] ?? 3); 43echo PHP_EOL; 44var_dump(foobar()[0] ?? false); 45echo PHP_EOL; 46function f($x) 47{ 48 printf("%s(%d)\n", __FUNCTION__, $x); 49 return $x; 50} 51 52$a = f(null) ?? f(1) ?? f(2); 53?> 54--EXPECTF-- 55int(3) 56 57int(7) 58int(3) 59 60int(7) 61int(3) 62int(7) 63int(3) 64 65int(7) 66string(3) "bar" 67int(3) 68object(stdClass)#%d (%d) { 69 ["boo"]=> 70 int(7) 71} 72string(4) "bang" 73int(3) 74 75called 76string(1) "a" 77 78f(0) 79f(1) 80