From:             [EMAIL PROTECTED]
Operating system: Linux
PHP version:      4.0.3pl1
PHP Bug Type:     Scripting Engine problem
Bug description:  Referenced variables and unset()

I found another bug (see id #8937) in connection with unset(). [Unset dosnīt work 
properly since august 1999]

<?

function test(&$bla) {
   unset($bla);
   $bla="huhu";
}

$bla="HIHI";

test($bla);

echo $bla;

?>

This will return "HIHI" instead of an expected "" or "huhu".

This bug exists cause unset() unsets the reference to $bla, not $bla itself. This also 
depends the GLOBAL-statement (see #8937)!

This is a bug, cause it is against the PHP-concept of making no big difference between 
reference and value
[ $bla=1; $hugo=&$bla; $hugo=2 is in the sight of $bla the same as $bla=1; $bla=2; ]

If I want to delete &$bla the correct expression is unset(&$bla). unset($bla) has 
always to delete the value
and all references to it. (that's just my opinion :-)

A fix of this bug will produce some compatibility problems with scripts, which has 
been written into PHP4 (cause the bug is very old).
But a fix should be done, cause many developers won't mind, that unseting a reference 
is in the sight of PHP a completly other thing than unseting a value.
There should be no/very less problems with upgrading PHP3-scripts.

PS: Just a small thought. In autumn last year I programmed constructs like the 
following
<?
$bla=array(1,array(1,array(1,2,3),3),3);
$ref=&$bla[2][2];
unset($ref);
?>
And I wondered, that this won't work as expected. Now I know why.
A correct solution would be to unset the inner array(1,2,3) and $ref... any other 
behaviour will break the mentioned handling of PHP.

Thougth 2:
<?
$bla="HIHI";
$ref=&$bla;
unset($ref);
$ref="huhu";
?>
What is the correct value of $bla. "" (empty) or "huhu"?



-- 
Edit Bug report at: http://bugs.php.net/?id=8972&edit=1



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