I threw this together to encompass the whole system. Hopefully this provides enough information.

#!/usr/bin/perl -w

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

### BEGINNING STRUCTURE
my %t_type = (

    'a' => {
        one => {low => 1000, high => 3000, percent => 25},
        two => {low => 200,high => 2000, percent => 30},
        three => {low => 1000,high => 6000, percent => 40},
        four => {low => 300,high => 1800, percent => 35},
        five => {low => 10, high => 40, percent => 60},
        six => {low => 2, high => 12, percent => 50},
        seven => [
            {select => 'small',low => 3,high => 3,percent => 30},
        ],
    },
    
    'b' => {
        one => {low => 1000, high => 3000, percent => 25},
        two => {low => 200,high => 2000, percent => 30},
        three => {low => 1000,high => 6000, percent => 40},
        four => {low => 300,high => 1800, percent => 35},
        five => {low => 10, high => 40, percent => 60},
        six => {low => 2, high => 12, percent => 50},
        seven => [
            {select => 'medium',low => 1,high => 1,percent => 10},
            {select => 'large',low => 1,high => 1,percent => 10},
        ],
    },
);

print "\t BEFORE\n";
print "data...\n";
print "$t_type{'b'}{'seven'}[0]->{'select'} \n";

foreach my $item ( @{$t_type{b}{seven}} ) {  
    print "... $item->{'select'}\n";
}


print "\n\t AFTER\n";
print "creating file...\n";

my $xsimple = XML::Simple->new();

open(L, ">tt.xml");
print L $xsimple->XMLout(\%t_type,
                       noattr => 1,
                       xmldecl => '<?xml version="1.0"?>',
                       GroupTags => { 'seven' => 'select' }
                       );       
close(L);

print "reading file...\n";

%t_type = ();

my $t_type = XMLin('tt.xml',GroupTags => { 'seven' => 'select' });
%t_type = \$t_type;
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%t_type = \$t_type;
How do I dereference back into the original structure? So I can access it the same way?

### lets test that returned structure
# yep its the same. must be a referrence problem?
print "dumping structure...\n";
print Dumper($t_type);
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It appears to print the original hash except for the $VAR1 not being $t_type.
Then try to print it the same as before but doesn't work.


print "data...\n";

print "$t_type{'b'}{'seven'}[0]->{'select'} \n";

foreach my $item ( @{$t_type{b}{seven}} ) {  
    print "... $item->{'select'}\n";
}
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What do I need to do?

I think you just have to dereference t_type.

...
my $t_type = XMLin('tt.xml',GroupTags => { 'seven' => 'select' });
%t_type = %$t_type;
[download]

was that the question?
Boris

You can do what you want, fairly simply, with XML::Writer. The result can be read back with XML::Parser.

First you have to decide what kind of XML you're going to write. That means settling on a DOCTYPE declaration or a schema of some kind. What are XML tags and what are data in your hash?

Once you have a doctype to settle that, the rest is easy. Note that since hash keys are unordered, they should be represented by XML that is also independent of order. Where order matters, arrays are used.

I recommend Perl & XML by Ray & McIntosh (O'Reilly, 2002) to get you started. Whatever you do, make absolutely sure that what you write is truly compliant XML and not some creole of it.

  use XML::Smart ;

  my $xml = new XML::Smart() ;
  
  $xml->{hash} = \%t_type ;
  
  $xml->save('hash.xml') ;
  
  my $xml_load = new XML::Smart('hash.xml') ;
  
  my %t_type_load = %{ $xml_load->tree_ok->{hash} } ;
  
  use Data::Dumper ;
  print Dumper( \%t_type_load ) ;
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