I am starting to think that this is a bug in XML::Dumper. I followed the Perl debugger and found this oddity: 
...

main::(foo.pl:16): $config = $dumper->xml2pl($xml);
  DB<1> s
XML::Dumper::xml2pl(.../XML/Dumper.pm:114):
114:     my ($obj,$tree) = @_;
  DB<1> n
XML::Dumper::xml2pl(.../XML/Dumper.pm:117):
117:     my $TopItem = $tree->[1];
  DB<1> n
XML::Dumper::xml2pl(.../XML/Dumper.pm:118):
118:     my $ref = &Undump($TopItem);
  DB<1> s
XML::Dumper::Undump(.../XML/Dumper.pm:133):
133:     my ($Tree) = shift;
  DB<1> n
XML::Dumper::Undump(.../XML/Dumper.pm:134):
134:     my $ref = undef;
  DB<1> n
XML::Dumper::Undump(.../XML/Dumper.pm:135):
135:     my $FoundScalar;
  DB<1> n
XML::Dumper::Undump(.../XML/Dumper.pm:136):
136:     my $i;
  DB<1> n
XML::Dumper::Undump(.../XML/Dumper.pm:138):
138:     for ($i = 1; $i < $#$Tree; $i+=2) {  
  DB<1> n
XML::Dumper::Undump(.../XML/Dumper.pm:178):
178:     $ref = $FoundScalar unless defined($ref);
  DB<1> n
XML::Dumper::Undump(/.../XML/Dumper.pm:180):
180:   done:
181:     return ($ref);
  DB<1> n
XML::Dumper::xml2pl(/.../XML/Dumper.pm:120):
120:     return($ref);
  DB<1> n
main::(foo.pl:21): print Dumper $config;

[download]
The problems i see are on lines 117 and 138 of XML/Dumper.pm. The code expects the argument to xml2pl to be an array ref, when it is really a scalar. The result is the for loop not being entered, and eventually an undef is returned.

Additionally, the synopsis code is inconsistent (if not broken) and once i 'fixed' and ran it, it produced the same results as your script - undef for the return value of xml2pl.

Personally, i'd just use XML::Simple. There maybe more configuration options to worry about, but i also think that you should worry about those config options.

My apologies in advance to the author of XML::Dumper if i am wrong. If nobody tells me contrary within about 24 hours then i will notify the author.

Update - i received a /msg from blakem that stated the same conclusion.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: XML::Dumper by jeffa
in thread Problems with XML::Dumper by theguvnor

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