#!/bin/perl
use strict;
use warnings;
use XML::Twig;

my $twig_handlers = {
                     'panoply/classes' => \&class_info,
                     'panoply/files' => \&file_info,
                     'panoply/namespaces' => \&namespace_info,
                    };

        
my $twig1;
my @xfiles = @ARGV;
foreach my $xfile (@xfiles) {
  $twig1 = new XML::Twig(ignore_elts => { brief => 'discard', detailed
+ => 'discard', includes => 'discard', included_by => 'discard', reimp
+lemented_by => 'discard' }, TwigRoots => {panoply => 1}, TwigHandlers
+ => $twig_handlers);
  eval { $twig1->parsefile( $xfile ) };
  die "can't parse file: $@" if $@;
}

sub class_info {
  my ($twig, $class) = @_;
  $class->set_pretty_print( 'indented' );
  $class->print;
}

sub file_info {
  my ($twig, $file) = @_;
  $file->set_pretty_print( 'indented' );
  $file->print;
}

sub namespace_info {
  my ($twig, $nsp) = @_;
  $nsp->set_pretty_print( 'indented' );
  $nsp->print;
}
[download]

<panoply>
  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public"/>
    <all_members name="DDR_VIA_JTAG" protection="public"/>
    <brief></brief>
    <detailed>
      <doc type="text">Models the access logic</doc>
    </detailed>
    <includes name="AccessLogic.hpp" local="no" />
    <public_methods>
      <members name="handledErrors" const="yes" kind="function" protec
+tion="public" static="no">
      </members>
      <members name="AccessLogic" const="no" kind="function" protectio
+n="public" static="no">
        <parameters declaration_name="accessLogic" type="AccessLogicTy
+pes" />
        <parameters declaration_name="handledErrors" type="const Handl
+edErrors &amp;" />
      </members>
    </public_methods>
    <public_typedefs>
      <members name="AccessLogicTypes" kind="enum" protection="public"
+>
        <values name="IO_CF8_CFC">
        </values>
      </members>
      <members name="MJTAG" kind="enumvalue">
      </members>
    </public_typedefs>
  </classes>
  <classes name="Panoply::Details::ActionBatch">
    <detailed></detailed>
    <includes name="PlatformActionBatch.hpp" local="no" />
  </classes>
  <classes name="Panoply::Details::ActionResult">
    <derived name="Panoply::Details::CPUIDActionResult"/>
    <includes name="PlatformAction.hpp" local="no" />
  </classes>
  <classes name="Panoply::Details::AddressIndex">
    <includes name="Panoply.hpp" local="no" />
  </classes>
  <files name="panoplydoc.hpp">
  </files>
  <files name="PanoplyExports.hpp">
     <defines>
      <members name="NOMINMAX" kind="define" protection="public">
      </members>
      <members name="_SCL_SECURE_NO_WARNINGS" kind="define">
      </members>
    </defines>
  </files>
  <namespaces name="AMD">
    <namespaces name="AMD::RegisterDef" />
  </namespaces>
  <namespaces name="AMD::RegisterDef">
    <classes name="AMD::RegisterDef::BaseDevice" />
    <enums>
      <members name="PermissionLevel" kind="enum" protection="public">
        <values name="PERMISSION_PUBLIC" initializer=" 10">
        </values>
        <values name="PERMISSION_NDA" initializer=" 20">
        </values>
      </members>
      <members name="RegisterType" kind="enum" protection="public">
        <values name="REGISTER_PCI" initializer=" 0">
        </values>
        <values name="REGISTER_MSR" initializer=" 1">
        </values>
      </members>
    </enums>
    <functions>
      <members name="Compare" const="no" kind="function" protection="p
+ublic">
        <parameters declaration_name="first" type="T" />
        <parameters declaration_name="second" type="T" />
      </members>
    </functions>
  <namespaces name="AMD::RegisterDef::Buffalo" />
    <variables>
      <members name="LIBRARY_VERSION">
      </members>
    </variables>
  </namespaces>
  <namespaces name="AMD::RegisterDef::Buffalo">
    <classes name="AMD::RegisterDef::Buffalo::BaseEntity" />
  </namespaces>
</panoply>
[download]

Sure, sprint, aka outer_xml

use strict; use warnings;
use XML::Twig;
my $twig = XML::Twig->new(
    pretty_print => 'indented',
    TwigHandlers => {
        ro => \&ssprint,
        sham => \&ssprint,
        bo => \&ssprint,
    }
);

$twig->xparse('<hi>
<ro><yo/></ro>
<sham><yo/></sham>
<bo><yo/></bo>
</hi>'
);

sub ssprint { print 'moo', $_->sprint, "\n"; }
__END__
moo
  <ro>
    <yo/>
  </ro>
moo
  <sham>
    <yo/>
  </sham>
moo
  <bo>
    <yo/>
  </bo>
[download]

So whatever it is you're trying to get done, might be written as

#!/usr/bin/perl --
use strict; use warnings;
use XML::Twig;
use Data::Dump qw' dd ';

Main( @ARGV );
exit( 0 );

sub Main {
    
    my %files;
    my $filename;
    my $ssprint = sub {
        # my( $twig, $elt ) = @_;
        # my( $twig, $_ ) = @_;
        # $_ is $elt
        push @{ $files{ $filename }{ $_->path } }, $_->sprint;
        return;
    };
    
    my $twig = XML::Twig->new(
        pretty_print => 'indented',
        TwigHandlers => {
            'panoply/classes'    => $ssprint,
            'panoply/files'      => $ssprint,
            'panoply/namespaces' => $ssprint,
        },
    );
    
    for my $file( @_ ){
        dd
        $filename = $file; ##
        
        eval {
            $twig->parsefile( $file );
            1;
        } or warn "ERROR parsefile($file): $@ ";
        $twig->purge;
    }
    dd \%files;
}


__END__
"panolpy.985318.xml"
"panolpy.985465.xml"
{
  "panolpy.985318.xml" => {
                            "/panoply/classes" => [
                                                    "\n  <classes name
+=\"Panoply::AccessLogic\">\n    <all_members name=\"accessLogic\" pro
+tection=\"public\" scope=\"Panoply::AccessLogic\" virtualness=\"non_v
+irtual\"/>\n    <all_members name=\"DBUS\" protection=\"public\" scop
+e=\"Panoply::AccessLogic\" virtualness=\"non_virtual\"/>\n    <all_me
+mbers name=\"DDR_VIA_JTAG\" protection=\"public\" scope=\"Panoply::Ac
+cessLogic\" virtualness=\"non_virtual\"/>\n    <all_members name=\"DE
+FAULT\" protection=\"public\" scope=\"Panoply::AccessLogic\" virtualn
+ess=\"non_virtual\"/>\n    <brief></brief>\n    <detailed>\n      <do
+c type=\"text\">Models the access logic</doc>\n    </detailed>\n    <
+includes local=\"no\" name=\"AccessLogic.hpp\"/>\n    <private_member
+s>\n      <members kind=\"variable\" name=\"m_accessLogic\" protectio
+n=\"private\" static=\"no\" type=\"AccessLogicTypes\" virtualness=\"n
+on_virtual\"></members>\n      <members kind=\"variable\" name=\"m_ha
+ndledErrors\" protection=\"private\" static=\"no\" type=\"HandledErro
+rs\" virtualness=\"non_virtual\"></members>\n    </private_members>\n
+    <public_methods>\n      <members const=\"yes\" kind=\"function\" 
+name=\"accessLogic\" protection=\"public\" static=\"no\" type=\"Acces
+sLogicTypes\" virtualness=\"non_virtual\" volatile=\"no\">\n        <
+brief></brief>\n        <detailed>\n          <doc type=\"text\">Gets
+ the current access logic for...</doc>\n        </detailed>\n      </
+members>\n      <members const=\"no\" kind=\"function\" name=\"Access
+Logic\" protection=\"public\" static=\"no\" virtualness=\"non_virtual
+\" volatile=\"no\">\n        <parameters declaration_name=\"accessLog
+ic\" default_value=\"DEFAULT\" type=\"AccessLogicTypes\"/>\n        <
+parameters declaration_name=\"handledErrors\" default_value=\"Handled
+Errors::ALL\" type=\"const HandledErrors &amp;\"/>\n      </members>\
+n    </public_methods>\n    <public_typedefs>\n      <members kind=\"
+enum\" name=\"AccessLogicTypes\" protection=\"public\" static=\"no\" 
+virtualness=\"non_virtual\">\n        <values name=\"DEFAULT\"></valu
+es>\n        <values name=\"IO_CF8_CFC\"></values>\n      </members>\
+n    </public_typedefs>\n  </classes>",
                                                    "\n  <classes name
+=\"Panoply::Details::ActionBatch\">\n    <brief></brief>\n    <detail
+ed></detailed>\n    <includes local=\"no\" name=\"PlatformActionBatch
+.hpp\"/>\n  </classes>",
                                                  ],
                            "/panoply/files"   => [
                                                    "\n  <files name=\
+"panoplydoc.hpp\">\n    <detailed></detailed>\n  </files>",
                                                    "\n  <files name=\
+"PanoplyVersion.hpp\">\n    <brief></brief>\n    <includes name=\"str
+ing\"/>\n    <variables>\n      <members initializer=\"&quot;0.1.9&qu
+ot;\" kind=\"variable\" name=\"LIBRARY_VERSION\" static=\"no\" type=\
+"const std::string\"></members>\n      <members initializer=\"&quot;0
+0/00/0000&quot;\" kind=\"variable\" name=\"BUILD_DATE\" static=\"no\"
+ type=\"const std::string\"></members>\n    </variables>\n  </files>"
+,
                                                  ],
                          },
  "panolpy.985465.xml" => {
                            "/panoply/classes"    => [
                                                       "\n  <classes n
+ame=\"Panoply::AccessLogic\">\n    <all_members name=\"accessLogic\" 
+protection=\"public\"/>\n    <all_members name=\"DDR_VIA_JTAG\" prote
+ction=\"public\"/>\n    <brief></brief>\n    <detailed>\n      <doc t
+ype=\"text\">Models the access logic</doc>\n    </detailed>\n    <inc
+ludes local=\"no\" name=\"AccessLogic.hpp\"/>\n    <public_methods>\n
+      <members const=\"yes\" kind=\"function\" name=\"handledErrors\"
+ protection=\"public\" static=\"no\"></members>\n      <members const
+=\"no\" kind=\"function\" name=\"AccessLogic\" protection=\"public\" 
+static=\"no\">\n        <parameters declaration_name=\"accessLogic\" 
+type=\"AccessLogicTypes\"/>\n        <parameters declaration_name=\"h
+andledErrors\" type=\"const HandledErrors &amp;\"/>\n      </members>
+\n    </public_methods>\n    <public_typedefs>\n      <members kind=\
+"enum\" name=\"AccessLogicTypes\" protection=\"public\">\n        <va
+lues name=\"IO_CF8_CFC\"></values>\n      </members>\n      <members 
+kind=\"enumvalue\" name=\"MJTAG\"></members>\n    </public_typedefs>\
+n  </classes>",
                                                       "\n  <classes n
+ame=\"Panoply::Details::ActionBatch\">\n    <detailed></detailed>\n  
+  <includes local=\"no\" name=\"PlatformActionBatch.hpp\"/>\n  </clas
+ses>",
                                                       "\n  <classes n
+ame=\"Panoply::Details::ActionResult\">\n    <derived name=\"Panoply:
+:Details::CPUIDActionResult\"/>\n    <includes local=\"no\" name=\"Pl
+atformAction.hpp\"/>\n  </classes>",
                                                       "\n  <classes n
+ame=\"Panoply::Details::AddressIndex\">\n    <includes local=\"no\" n
+ame=\"Panoply.hpp\"/>\n  </classes>",
                                                     ],
                            "/panoply/files"      => [
                                                       "\n  <files nam
+e=\"panoplydoc.hpp\"></files>",
                                                       "\n  <files nam
+e=\"PanoplyExports.hpp\">\n    <defines>\n      <members kind=\"defin
+e\" name=\"NOMINMAX\" protection=\"public\"></members>\n      <member
+s kind=\"define\" name=\"_SCL_SECURE_NO_WARNINGS\"></members>\n    </
+defines>\n  </files>",
                                                     ],
                            "/panoply/namespaces" => [
                                                       "\n  <namespace
+s name=\"AMD\">\n    <namespaces name=\"AMD::RegisterDef\"/>\n  </nam
+espaces>",
                                                       "\n  <namespace
+s name=\"AMD::RegisterDef\">\n    <classes name=\"AMD::RegisterDef::B
+aseDevice\"/>\n    <enums>\n      <members kind=\"enum\" name=\"Permi
+ssionLevel\" protection=\"public\">\n        <values initializer=\" 1
+0\" name=\"PERMISSION_PUBLIC\"></values>\n        <values initializer
+=\" 20\" name=\"PERMISSION_NDA\"></values>\n      </members>\n      <
+members kind=\"enum\" name=\"RegisterType\" protection=\"public\">\n 
+       <values initializer=\" 0\" name=\"REGISTER_PCI\"></values>\n  
+      <values initializer=\" 1\" name=\"REGISTER_MSR\"></values>\n   
+   </members>\n    </enums>\n    <functions>\n      <members const=\"
+no\" kind=\"function\" name=\"Compare\" protection=\"public\">\n     
+   <parameters declaration_name=\"first\" type=\"T\"/>\n        <para
+meters declaration_name=\"second\" type=\"T\"/>\n      </members>\n  
+  </functions>\n    <namespaces name=\"AMD::RegisterDef::Buffalo\"/>\
+n    <variables>\n      <members name=\"LIBRARY_VERSION\"></members>\
+n    </variables>\n  </namespaces>",
                                                       "\n  <namespace
+s name=\"AMD::RegisterDef::Buffalo\">\n    <classes name=\"AMD::Regis
+terDef::Buffalo::BaseEntity\"/>\n  </namespaces>",
                                                     ],
                          },
}
[download]

Thanks, works great but I am not familiar how to extract info from this type of hash. For example, output appears to be an anonymous hash, a string, anonymous hash, string, then array. How do I extract arrays of info. Tried variations of $key->{}->{}->[0] but no luck.

{
  "xmlout.xml" => {
    "/panoply/classes"    => [
                               "\n  <classes name=\"Panoply::AccessLog
+ic\">\n    <all_members name=\"accessLogic\" protection=\"public\" sc
+ope=\"Panoply::AccessLogic\" virtualness=\"non_virtual\"/>\n   </clas
+ses>",
                               "\n  <classes name=\"Panoply::Details::
+ActionBatch\"></classes>",
                             ],                               
    "/panoply/files"      => [
                               "\n  <files name=\"AccessLogic.hpp\"></
+files>",
                               "\n  <files name=\"BaseDevice.h\"></fil
+es>",
                             ],
    "/panoply/namespaces" => [
                               "\n  <namespaces name=\"std\"></namespa
+ces>",
                             ],
  },
}
[download]