In the process of working on another problem, I found the 'keyattr' bit of XML::Simple, and the FAQ that talks about 'array folding'. I cooked up this small snippet, which causes XML::Simple to throw an Out of memory! error. If I set 'forcearray' to 0, disabling it (against the recommended behavior), the error goes away.

What I want to know is.. why?

Obligatory Code 

use strict;
use warnings;
use XML::Simple;
use Data::Dumper;

my $xml = XMLin(\*DATA,         keyattr    => ['url'],
                                forcearray => '1');   

print Dumper($xml);
print "URL: $xml->{bar}->{blort}->{quux}->{url}\n";

__DATA__
<?xml version="1.0" encoding="iso-8859-2"?>
<foo>
  <bar>
    <blort>
      <quux>
        <url>http://f.co/index.html</url>
      </quux>
    </blort> 
  </bar>
</foo>

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In reply to XML::Complicated by hacker

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