ArrayByRef.php

<?php
$sets = array();

$fruit = array('apples', 'grapes');
$numbers = array('one', 'two', 'three');

$sets[] = &$fruit;
$sets[] = &$numbers;

$fruit[] = 'banana';
$numbers[] = 'four';

$sets[] = &$sets[count($sets)-1];
$sets[] = end($sets);

$numbers[] = 'five';

foreach($sets as $set) {
	var_dump($set);
}

Output.txt

array(3) {
  [0]=>
  string(6) "apples"
  [1]=>
  string(6) "grapes"
  [2]=>
  string(6) "banana"
}
array(5) {
  [0]=>
  string(3) "one"
  [1]=>
  string(3) "two"
  [2]=>
  string(5) "three"
  [3]=>
  string(4) "four"
  [4]=>
  string(4) "five"
}
array(5) {
  [0]=>
  string(3) "one"
  [1]=>
  string(3) "two"
  [2]=>
  string(5) "three"
  [3]=>
  string(4) "four"
  [4]=>
  string(4) "five"
}
array(4) {
  [0]=>
  string(3) "one"
  [1]=>
  string(3) "two"
  [2]=>
  string(5) "three"
  [3]=>
  string(4) "four"
}