perl with xml : why to I need check if the Attribute is defined, shouldn't $node->attributes already do that? -

i'm trying use perl parse xml , i've run across seems odd. when call $node->attributes() seems return undefined value in cases. if @ line labeled problem, can see if i've added. have thought that if node had no attributes foreach wouldn't have had loop on. if uncomment if on line works. (i know put check outside loop, i'm wondering why need check @ all)

#!/usr/bin/perl  use strict; use warnings;  $filename = 'lib.xml'; use xml::libxml;  $parser = xml::libxml->new(); $parser->keep_blanks(0);  $doc    = $parser->parse_file($filename);  sub process_node {     $level = shift;     $node = shift;      printf ("%*s", $level, "");     print $node->nodename;     print "<", $node->nodevalue,">" if (defined($node->nodevalue));     print "\n";      print "attrs:\n";      foreach ($node->attributes()){     print $_->name,":",$_->value," " ;# if (defined($_)); ### problem     }      print "\n";      $child ($node->childnodes) {         process_node($level+1, $child);     } }  process_node(1, $doc->documentelement); 

here's contents of lib.xml:

<data size="4"> <stuff src="one" dst="two" /> hmm </data> 

and here's "bad" output:

>>> ./xml.pl   data attrs: size:4    stuff attrs: src:one dst:two    text< hmm > attrs: can't call method "name" on undefined value @ ./xml.pl line 26. 

and when uncomment if

>>> ./xml.pl   data attrs: size:4    stuff attrs: src:one dst:two    text< hmm > attrs: 

this because of believe bug in xml::libxml::text::attributes, looks this

sub attributes { return undef; } 

this should be

sub attributes { return } 

which return undef in scalar context , empty list in list context

you can fix if want. in latest version of module -- 2.0123 -- it's on line 1789 of libxml.pm in xml::libxml installation. can discover file running

perldoc -l xml::libxml 

i raise bug report maintainers