1--TEST-- 2foreach with iterator and &$value reference 3--FILE-- 4<?php 5 6class MyIterator implements Iterator { 7 public function valid(): bool { return true; } 8 public function next(): void {} 9 public function rewind(): void {} 10 public function current(): mixed { return null; } 11 public function key(): mixed {return ""; } 12} 13 14$f = new MyIterator; 15echo "-----( Try to iterate with &\$value: )-----\n"; 16foreach ($f as $k=>&$v) { 17 echo "$k => $v\n"; 18} 19 20?> 21--EXPECTF-- 22-----( Try to iterate with &$value: )----- 23 24Fatal error: Uncaught Error: An iterator cannot be used with foreach by reference in %s:13 25Stack trace: 26#0 {main} 27 thrown in %s on line 13 28