ID: 32840
User updated by: wagner at bonn dot edu
Reported By: wagner at bonn dot edu
Status: Bogus
Bug Type: Scripting Engine problem
Operating System: *
PHP Version: 4.3.11, 5.0.4
New Comment:
So static is implemented through references. Big deal.
What does that have to do with this bug?
Why does only one of the two functions in the example
return a reference, although both use a static variable?
The problem can be reproduced without static or global
anyway:
Reproduce code:
---------------
function incr(&$int) {
return $int++;
}
function f(&$v) {
$cache = $v[0];
return($cache);
}
$v = array();
$v[0] = 1;
echo "f: ".incr(f($v)).incr(f($v))."\n";
Expected result:
----------------
f: 11
return by value, no effect on $v
Actual result:
--------------
f: 12
return by reference
------------
How does incr() get its hands on $v here? f() should
return a copy of $cache, which should be a copy too.
This is apparently not a problem with static, but with how
array (and object) are implemented in the ZE, and I find
no mention whatsoever in the manual about that, so this
is at least a documentation problem.
Would you please take a good look at what I'm trying to
explain here and reopen the bug?
Previous Comments:
------------------------------------------------------------------------
[2005-04-27 12:52:26] [EMAIL PROTECTED]
RTFM:
http://www.php.net/manual/en/language.variables.scope.php
And the part with title:
"References with global and static variables"
------------------------------------------------------------------------
[2005-04-26 14:55:47] wagner at bonn dot edu
probably related to http://bugs.php.net/bug.php?id=32841
which also shows the broken behaviour for actual member
variables
------------------------------------------------------------------------
[2005-04-26 14:39:33] wagner at bonn dot edu
The Expected result should actually look like this:
---------------------------------------------------
f1: 11
f2: 11
------------------------------------------------------------------------
[2005-04-26 14:37:52] wagner at bonn dot edu
Description:
------------
Returning a value of an array or a member-variable causes
the return to be by reference. This also happens in PHP
4.3.x
Related to http://bugs.php.net/bug.php?id=32789 which
seems bogusified beyond repair.
Reproduce code:
---------------
function incr(&$int) {
return $int++;
}
function f() {
static $v;
if (!$v)
$v = 1;
return($v);
}
function f2() {
static $v;
if (!$v) {
$v = array();
$v[0] = 1;
}
return($v[0]);
}
echo "f1: ".incr(f()).incr(f())."\n";
echo "f2: ".incr(f2()).incr(f2())."\n";
Expected result:
----------------
f1: 11
f2: 12
Same behaviour for both functions.
Actual result:
--------------
f1: 11
f2: 12
f2 inexplicably returns a reference.
The manual states that for this to happen, it should be
necessary to actually use a & in front of the definition
of the returning function:
http://de2.php.net/manual/en/language.references.return.php
"... you have to use & in both places - to indicate that
you return by-reference, not a copy as usual, and to
indicate that reference binding, rather than usual
assignment, should be done ..."
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=32840&edit=1
