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Bug #19943 Ragged array returns undefined results
Submitted: 2002-10-16 19:50 UTC Modified: 2003-03-06 12:45 UTC
Votes:1
Avg. Score:1.0 ± 0.0
Reproduced:0 of 1 (0.0%)
From: su-php at bossi dot com Assigned:
Status: Closed Package: Scripting Engine problem
PHP Version: 4.3.2-dev OS: Win2K
Private report: No CVE-ID: None
View Developer Edit
 [2002-10-16 19:50 UTC] su-php at bossi dot com 
When using an array that has ragged indices, the value in the array is undefined. Well, actually it can be defined, but it is unexpected. No errors or warnings are reported. Sample Code:

<?
$ragged = array();
for ( $count = 0; $count < 10; $count++ )
{
	$ragged[$count]        = 'single '.$count;
	$ragged[$count]['idx'] = 'ragged '.$count;
}
?>
<html><head></head><body>
<table border="1">
<tr>
	<td>Expected</td><td>Actual</td>
	<td>Expected IDX</td><td>Actual IDX</td>
</tr>
<?
for ( $count = 0; $count < 10; $count++ )
{
?>
<tr>
	<td> <?= 'single '.$count ?> </td><td> <?= $ragged[$count] ?> </td>
	<td> <?= 'ragged '.$count ?> </td><td> <?= $ragged[$count]['idx'] ?> </td>
</tr>
<? } ?>
</table></body></html>

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 [2002-10-16 19:54 UTC] su-php at bossi dot com 
However, the following codes does work, even though the array is still ragged:
<?
$ragged = array();
for ( $count = 0; $count < 10; $count++ )
{
	$ragged['idx'][$count] = 'ragged '.$count;
	$ragged[$count]        = 'single '.$count;
}
?>
<html><head></head><body>
<table border="1">
<tr>
	<td>Expected</td><td>Actual</td>
	<td>Expected IDX</td><td>Actual IDX</td>
</tr>
<?
for ( $count = 0; $count < 10; $count++ )
{
?>
<tr>
	<td> <?= 'single '.$count ?> </td><td> <?= $ragged[$count] ?> </td>
	<td> <?= 'ragged '.$count ?> </td><td> <?= $ragged['idx'][$count] ?> </td>
</tr>
<? } ?>
</table></body></html>
 [2002-10-16 22:51 UTC] iliaa@php.net 
A pretty interesting bug this is, there appear to be 2 possible behaviours that can happen here and only 1 is correct.
<?php

$ar = array();
for ( $count = 0; $count < 10; $count++ )
{
        $ar[$count]        = "$count";
        $ar[$count]['idx'] = "$count";
}

for ( $count = 0; $count < 10; $count++ )
{
        echo $ar[$count]." -- ".$ar[$count]['idx']."\n";
}
?>

The code above will output:
t 0 -- t
t 1 -- t
t 2 -- t
t 3 -- t
t 4 -- t
t 5 -- t
t 6 -- t
t 7 -- t
t 8 -- t
t 9 -- t
/home/rei/PHP_CVS/php4/Zend/zend_operators.c(1008) :  Freeing 0x08369384 (6 bytes), script=a.php
Last leak repeated 9 times

If the " around the $count variable are removed then the script reports:
Warning: Cannot use a scalar value as an array in /home/rei/PHP_CVS/php4/a.php on line 7
/home/rei/PHP_CVS/php4/a.php(7) : Warning - Cannot use a scalar value as an array

for every assignment and does no initialize any of the $ar[$count]['idx'] values.
 [2002-10-30 07:30 UTC] Ppslim at ntlworld dot com 
I think this is pretty much invalid.

su-php@bossi.com posted 2 examples. Only 1 is correct, or infact, valid code.

In the first example, you have the following 2 array assignments.

$ragged[$count]        = 'single '.$count;
$ragged[$count]['idx'] = 'ragged '.$count;

In this, you assign a string to $ragged[$count], then, you turn it into an array using $regged[$count]['idx'].

This is invlaid in most languages.

In the $ragged[$count], $ragged['idx'][$count] method, no type changes are taking place.
 [2002-11-05 13:40 UTC] moriyoshi@php.net 
The reported behaviour itself is not a bug
(see http://lists.php.net/article.php?group=php.dev&article=90522 for detail), but the memory leaks imply another bug. So I decided to reclassify this as Scripting Engine problem, and change the status to "Analyzed".

Anyway thank you for the bug report!

--
Moriyoshi
 [2003-02-25 02:46 UTC] sniper@php.net 
Memleak still present in 4.3.2-dev.
 [2003-03-06 12:45 UTC] sniper@php.net 
Memleak fixed in CVS.
 
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