From: [EMAIL PROTECTED]
Operating system: unix
PHP version: 4.2.0
PHP Bug Type: Strings related
Bug description: isset() and empty() wrong behavior for empty part of string
The following program displays a notice (error_reporting is set to display
all warnings):
-------------
<pre>
<?php
$a='hugp';
for ($i=0; isset($a[$i]); $i++) {
echo "\nChar $i:$a[$i]";
}
?>
-------------
Displays the message
Notice: Uninitialized string offset: 4 ... line 4
This is a bug, cause isset() is used to determine, if $a[4] is set or not,
so there has to be no message, that a var is not set. It happens also, if
you write $a{$i} instead of $a[$i] (this is the syntax, which will only be
supported from PHP5 up).
Cause isset() is used in empty(), empty has also this bug.
This bug has already been reported (#16528), but has been closed - perhaps
due to completly other example (array depending). I have been told that
it's not a bug. But as you directly see with this example it is. I have
written a mail to Derick Redhans who cleaned it, that it might be a fault
to clean it, but never heard an answer.
Please fix this bug, cause programmers, who write the following:
$a='';
if ( !empty($a['bla']) )
will be complained with this Notice, even it is correct code (and maybe
that, what he wants). Of course it is correct to display the notice, if
you write:
echo $a['bla'];
---------
A small suggestion: Cause Zeev said on PHP-Congress, that the above syntax
(with [] instead of {}) to exercise a char in a string is not supported
any more in PHP5, it might be a very good idea to implement a switch,
which will warn if you use the syntax right now! This switch could also be
used, to warn the programmer for other incompatibilities... with PHP5.
--
Edit bug report at http://bugs.php.net/?id=16732&edit=1
--
Fixed in CVS: http://bugs.php.net/fix.php?id=16732&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=16732&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=16732&r=needtrace
Try newer version: http://bugs.php.net/fix.php?id=16732&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=16732&r=support
Expected behavior: http://bugs.php.net/fix.php?id=16732&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=16732&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=16732&r=submittedtwice
