Hello monks, I'm having difficulty with an XML file. The file is huge (140,000 lines or so) and I need to get a summary of it to build a database to fit the data. Basically, I'd like to get a Hash with keys of every element in the file mapped to values of how many times they occur. I've been trying to use Twig to extract the data and keep hitting a snag somewhere. I've read through the Camel book and the Twig tutorials, but this is the first Perl program I've ever written so I could really use some pointers. Here's what I've got so far. 
use XML::Twig;

my $twig=XML::Twig->new(   
    twig_handlers => 
      { title   => sub { $_->set_gi( 'h2') }, #  tags to h2
        para    => sub { $_->set_gi( 'p')  }, #  para to p
        populate=> sub { while (<>)
{ if (%Items !~ m/"<us:"|"<oa:"(.*)/) { $Items{$1} =1}  
else {$Items{$2} =($Items{$1}+(/$1/))
}

#If element is not in the hash, adds it 
#If element is in the hash, adds the number of matches to the value 
                         };
                        },           
    hidden  => sub { $_->delete;       }, # remove hidden elements
    list    => \&my_list_process,         # process list elements
    div     => sub { $_[0]->purge;     }, # free memory
      },
      );
                    
$twig->parsefile( 'bigXMLfile.xml'); # build it
print %Items;                        # output the twig
$twig->purge;                  # clear end of document from memory

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I don't think that the program is calling the handlers properly when the file is parsed. The strangest part is that it keeps returning a value of 1. Did I somehow put the populate sub into a Boolean context? What am I doing wrong? Is there an easier way to get what I'm after? Thanks!

In reply to Using XML Twig to summarize a large file by Mr.Churka

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