http://www.perlmonks.org?node_id=985787


in reply to Re^3: XML::Twig traversing tree and storing in an array
in thread XML::Twig traversing tree and storing in an array

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>",
                             ],
  },
}

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Re^5: XML::Twig traversing tree and storing in an array
by Anonymous Monk on Aug 07, 2012 at 07:44 UTC

    Tried variations of ....

    Why not post what you tried? 

    #!/usr/bin/perl --
use strict; use warnings;
my $foops = {
  "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>",
                             ],
  },
};

print $foops, "\n";
print $foops->{"xmlout.xml"}, "\n";
print $foops->{"xmlout.xml"}{"/panoply/classes"}, "\n";
print $foops->{"xmlout.xml"}{"/panoply/classes"}[0], "\n";
print $foops->{"xmlout.xml"}{"/panoply/classes"}[1], "\n\n";

use Data::Diver qw( Dive );
my $classes = Dive( $foops, "xmlout.xml", "/panoply/classes" );
print $classes, "\n";
print scalar @{$classes}, "\n";
print @{$classes}, "\n\n";

while( my( $filename, $datahash ) = each %$foops ){
    print "$filename => $datahash\n";
    while( my( $branchname, $brancharray ) = each %$datahash ){
        printf "%-20s => n(%3d) => %s\n",
            $branchname, scalar(@$brancharray), $brancharray;
    }
}

__END__
HASH(0x9ad1bc)
HASH(0x99a36c)
ARRAY(0x3f8a8c)

  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public" scope="Panoply
+::AccessLogic" virtualness="non_virtual"/>
   </classes>

  <classes name="Panoply::Details::ActionBatch"></classes>

ARRAY(0x3f8a8c)
2

  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public" scope="Panoply
+::AccessLogic" virtualness="non_virtual"/>
   </classes>
  <classes name="Panoply::Details::ActionBatch"></classes>

xmlout.xml => HASH(0x99a36c)
/panoply/namespaces  => n(  1) => ARRAY(0x99a2fc)
/panoply/files       => n(  2) => ARRAY(0x99a26c)
/panoply/classes     => n(  2) => ARRAY(0x3f8a8c)

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    Tutorials► Data Types and Variables ► Data Type: Array ► Data Type: Hash► References quick reference

[reply]
[d/l]
      Thanks again, learned more. Regarding your first code post where Main( @ARGV ); is used for providing multiple xml files on command line, is the most practical way of placing output from each file into a separate hash by duplicating "for my $file" and specify $_[0], $_1, etc. 
         for my $file( $_[0] ){
        # dd
        $filename = $file; ##
        
        eval {
            $twig->parsefile( $file );
            1;
        } or warn "ERROR parsefile($file): $@ ";
   }

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[reply]
[d/l]
        Here is what I am trying to achieve. Take C++ API generated from Doxygen into perl module output, convert to xml, filter xml, then put old and new version of API into hashes or arrays so I can compare and report what has changed in each class, namespace, etc. and new classes that have been added. Still working on comparison ideas. What I have so far. Must be better way to put output of test files into separate hashes and arrays instead of duplicating everything like I did. 
        #!/usr/bin/perl --
# use strict;
use warnings;
use XML::Simple;
use XML::Twig;
use Data::Dump qw' dd ';
my @panapi;
my @allclasses;
my @allfiles;
my @allnsp;
my %elements;
# require "DoxyDocs.pm";
# our $doxydocs;
#########################################
# Script takes DoxyDocs.pm converts to xml
# then filters out unneeded tags from xml
# then lists all classes, files, namespaces
# and separates each class, file, and namespace
# in hash on line with its related properties
#
# usage: apixml.pl xml1.xml xml2.xml > out.txt
#
#########################################
# my $fh = 'xmlout.xml';
# my $xs = new XML::Simple(RootName => "panoply");

# add the NoAttr => 1,  option to convert attributes to elements
# $xs->XMLout($doxydocs, XMLDecl => 1, OutputFile => $fh);

Main( @ARGV );
exit( 0 );

sub Main {
    
    my %oldfile;
    my %newfile;
    my %class;
    my $filename;
    my $ssprint = sub {
        my( $twig, $_ ) = @_;
        push @{ $oldfile{ $filename }{ $_->path } }, $_->sprint;  #sto
+re in hash
        # push (@panapi, $_->sprint);  # store in array instead
        return;
    };
    my $s2sprint = sub {
        my( $twig1, $_ ) = @_;
        push @{ $newfile{ $filename }{ $_->path } }, $_->sprint;  #sto
+re in hash
        # push (@panapi, $_->sprint);  # store in array instead
        return;
    };
    
    my $twig = XML::Twig->new(
        ignore_elts => { brief => 'discard', detailed => 'discard', in
+cludes => 'discard', included_by => 'discard', reimplemented_by => 'd
+iscard' },
        pretty_print => 'indented',
        TwigHandlers => {
            'panoply/classes'    => $ssprint,
            'panoply/files'      => $ssprint,
            'panoply/namespaces' => $ssprint,
        },
    );
    
    my $twig1 = XML::Twig->new(
        ignore_elts => { brief => 'discard', detailed => 'discard', in
+cludes => 'discard', included_by => 'discard', reimplemented_by => 'd
+iscard' },
        pretty_print => 'indented',
        TwigHandlers => {
            'panoply/classes'    => $s2sprint,
            'panoply/files'      => $s2sprint,
            'panoply/namespaces' => $s2sprint,
        },
    );
    
    for my $file( $_[0] ){
        # dd
        $filename = $file; ##
        
        eval {
            $twig->parsefile( $file );
            1;
        } or warn "ERROR parsefile($file): $@ ";
    
        my $root = $twig->root;
        my @class = $root->children( 'classes' );
        print "Previous version of API\n";
        foreach my $cls (@class) {
          my $clsname = $cls->{'att'}->{'name'};
          print "classes: $clsname\n";
          push (@allclasses, $clsname);
        }
        
        my @files = $root->children( 'files' );
        foreach my $file (@files) {
          my $filename = $file->{'att'}->{'name'};
          print "files: $filename\n";
          push (@allfiles, $filename);
        }

        my @namesp = $root->children( 'namespaces' );
        foreach my $nsp (@namesp) {
          my $name = $nsp->{'att'}->{'name'};
          print "namespaces: $name\n";
          push (@allnsp, $name);
        }
        $twig->purge;
    }
    dd \%oldfile;
    # dd \@panapi; # store in array instead
    
    for my $file1( $_[1] ){
        # dd
        $filename = $file1; ##
        
        eval {
            $twig1->parsefile( $file1 );
            1;
        } or warn "ERROR parsefile($file1): $@ ";
    
        my $root = $twig1->root;
        my @class = $root->children( 'classes' );
        print "\n\nNew version of API\n";
        foreach my $cls (@class) {
          my $clsname = $cls->{'att'}->{'name'};
          print "classes: $clsname\n";
          push (@allclasses, $clsname);
        }
        
        my @files = $root->children( 'files' );
        foreach my $file (@files) {
          my $filename = $file->{'att'}->{'name'};
          print "files: $filename\n";
          push (@allfiles, $filename);
        }

        my @namesp = $root->children( 'namespaces' );
        foreach my $nsp (@namesp) {
          my $name = $nsp->{'att'}->{'name'};
          print "namespaces: $name\n";
          push (@allnsp, $name);
        }
        $twig1->purge;
    }
    dd \%newfile;
}

        [download]
        Test files: 
        <?xml version='1.0' standalone='yes'?>
<panoply>
  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public"/>
    <all_members name="DDR_VIA_JTAG" protection="public" scope="Panopl
+y::AccessLogic" virtualness="non_virtual" />
    <all_members name="SPR" 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" />
      </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::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="_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>
</panoply>

        [download]
        File 2: 
        <?xml version='1.0' standalone='yes'?>
<panoply>
  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public"/>
    <all_members name="DDR_VIA_JTAG" protection="public"/>
    <all_members name="SPR" protection="public" scope="Panoply::Access
+Logic" />
    <all_members name="DBUS" 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>
  <files name="common.hpp">
  </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>
  <namespaces name="AMD::RegisterDef::Buffalo">
    <classes name="AMD::RegisterDef::Buffalo::BaseEntity" />
  </namespaces>
</panoply>

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