Syntax Bug, or Program Bug?
Filed in: PHP Add comments
So, while coding today I came across a very strange bug in PHP. It seems as though subtracting two arrays will return null.
However, if I wrap that in the floor() function, it works as expected.
Go figure. Took me 30 minutes to find that annoying bug.
September 28th, 2005 at 21:27 (9:27 pm)
Have you tried a simple test program to make sure you’re just not making too complicated a program?
105);
$foo2 = array(’two’=>159);
echo ‘$foo1[\'one\'] is ‘.$foo1['one'].”;
echo ‘$foo2[\'two\'] is ‘.$foo2['two'].”;
$result = $foo2['two'] - $foo1['one'];
echo ‘the result is ‘.$result;
?>
See how that runs…
September 29th, 2005 at 00:08 (12:08 am)
It seems to only do it with data in the $_POST variable.
And I think you’re comment got hosed…
September 29th, 2005 at 10:53 (10:53 am)
…
A little. The 105); was supposed to be the PHP start string. Everything else looks about right… :P
Oh, except this line was dropped in the beginning:
$foo1 = array(’one’=>102);
If it’s only in the $_POST variable, try this variation:
if (isset($_POST['one']) {
$foo2 = array(’two’=>159);
echo ‘$_POST[\’one\’] is ‘.$_POST[’one’].’’;
echo ‘$foo2[\’two\’] is ‘.$foo2[’two’].’’;
$result = $foo2[’two’] - $_POST[’one’];
echo ‘the result is ‘.$result;
} else {
echo ”;
}
?>
September 29th, 2005 at 10:55 (10:55 am)
Yeah, that got hosed as well. It’s not that hard to htmlspecialchars() and nl2br() a comment, is it? :P
The echo was supposed to be… convert () to brackets…
(form method=”post”)(input type=”text” name=”one”)(input type=”submit”)(/form)
September 29th, 2005 at 10:58 (10:58 am)
Ah, I see, it drops out wannabe HTML code. Why can’t it just print it? In the first comment it dropped out everything between (?php and $foo1=>105);. It saw the PHP tag’s bracket as the start, and the arrow/bracket in the => as the end tag.
Yuck. What a fucking mess… :P
September 29th, 2005 at 14:14 (2:14 pm)
yeah…it’s wordpress. I haven’t bothered to tweak it yet really. I’ll try your test case this weekend, and let you know.