Bug #70857 [Opn->Csd]: Foreach with a reference is modifying the result of a ternary expression
| From: | nikic@php.net | Date: | Tue, 31 Jan 2017 10:51:09 +0000 |
| Subject: | Bug #70857 [Opn->Csd]: Foreach with a reference is modifying the result of a ternary expression | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-207061@lists.php.net to get a copy of this message | ||
Edit report at https://bugs.php.net/bug.php?id=70857&edit=1
ID: 70857
Updated by: nikic@php.net
Reported by: nairebis at gmail dot com
Summary: Foreach with a reference is modifying the result of
a ternary expression
-Status: Open
+Status: Closed
Type: Bug
Package: Variables related
Operating System: CentOS 6.7
PHP Version: 5.6.15
-Assigned To:
+Assigned To: nikic
Block user comment: N
Private report: N
New Comment:
Closing as this is fixed in PHP 7 and PHP 5.6 is out of active support.
Previous Comments:
------------------------------------------------------------------------
[2015-11-05 01:37:01] bwoebi@php.net
This is fixed in PHP 7.
Also it has inconsistent behavior thanks to copy on write: https://3v4l.org/jMjc8#v550
------------------------------------------------------------------------
[2015-11-04 20:45:58] nairebis at gmail dot com
Description:
------------
Consider this line, where $a is an array:
foreach (1 ? $a : [] as &$x) {
According to the PHP documentation on ternary expressions, "Note: Please note that the ternary
operator is an expression, and that it doesn't evaluate to a variable, but to the result of an
expression. This is important to know if you want to return a variable by reference. The statement
return $var == 42 ? $a : $b; in a return-by-reference function will therefore not work and a warning
is issued in later PHP versions."
The result of the ternary expression should not be an lvalue, and thus the above shouldn't
work. But it actually does allow this.
Test script:
---------------
$a = [1, 2, 3, 4];
foreach (1 ? $a : [] as &$x) {
$x += 10;
}
print_r($a);
Expected result:
----------------
Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 4
)
Actual result:
--------------
Array
(
[0] => 11
[1] => 12
[2] => 13
[3] => 14
)
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=70857&edit=1