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Subject: Confusing pointers in PHP 4 and 5
From: taco@procurios.nl (Taco van den Broek)

While venus is crossing the sun I'm trying to model a tree using two 
arrays; one containing the structure of the tree and the other 
containing the data of the nodes.
The second array also contains pointers to 'subtrees' of the first 
array. Anyway, I discovered a strange behavior when I dumped the tree 
before and after making the pointers.
Example:

<?php
$tree = array( 1 => array( 2 => 'foo' ) );

var_dump($tree);

$b = &$tree[1];

var_dump($tree);
?>

This code will output the following:
array(1) {
   [1]=>
   array(1) {
     [2]=>
     string(3) "foo"
   }
}
array(1) {
   [1]=>
   &array(1) {
     [2]=>
     string(3) "foo"
   }
}

As you can see the original tree now contains a pointer, how can that 
be, I didn't change the original array!?
So what I'd like to know is: Is this intended behavior, and if so: why 
does it work like this and would it make some operations impossible?

Taco