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Doc Bug #29429 unset( $GLOBALS['foo']); unset only global variable, not variables that REFERED
Submitted: 2004-07-28 15:05 UTC Modified: 2004-07-29 10:04 UTC
From: kingoleg at mail dot ru Assigned:
Status: Not a bug Package: Documentation problem
PHP Version: 4.3.8 OS: All
Private report: No CVE-ID: None
View Developer Edit
 [2004-07-28 15:05 UTC] kingoleg at mail dot ru 
Description:
------------
unset( $GLOBALS['foo']); unset only global variable, not variables that REFERED to global variable

How we can unset global variable with all referenced variable using unset() function? Do we must user assign to null?

Reproduce code:
---------------
<?php
function a( &$foo) {
    $foo = 'ok';
    b( $foo);
    var_dump( $foo);
}

function b( &$foo) {
    $foo = 'not ok';
    unset( $GLOBALS['foo']);
}

global $foo;
$foo = 'global';
a($foo);
var_dump( $foo);

?>

Expected result:
----------------
NULL NULL

Actual result:
--------------
string(6) "not ok" NULL

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 [2004-07-29 09:23 UTC] tony2001@php.net 
It's a docu problem, not a bug.
 [2004-07-29 09:44 UTC] kingoleg at mail dot ru 
Doc problem about this http://bugs.php.net/?id=29428 was closed with bogus status :)
 [2004-07-29 09:51 UTC] tony2001@php.net 
Then it's a bogus docu problem.
 [2004-07-29 10:04 UTC] vrana@php.net 
This is slightly different. Explaining just here:

$foo inside a() is reference to value referenced also by $GLOBALS['foo']. $foo inside b() is the same. So there are 3 references to the value. Unseting $GLOBALS['foo'] inside b() destroys only one reference. Returning from b() destroys the second reference. But there still exists one reference to the value ($foo in a()), so var_dump() inside a() prints the value. Last reference is destroyed after returning from a(), so var_dump() outside function prints NULL.

You can understand what's happening if you understand the sentence "$a and $b are completely equal here, that's not $a is pointing to $b or vice versa, that's $a and $b pointing to the same place." written in the manual. So this is really bogus.
 
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