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Unsetting References

When you unset the reference, you just break the binding between variable name and variable content. This does not mean that variable content will be destroyed. For example:

<?php
$a = 1;
$b =& $a;
unset($a); 
?>
won't unset $b, just $a.

Again, it might be useful to think about this as analogous to the Unix unlink call.

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/language.references.unset.php