Oh great monks, I find I am needful your wisdom. I am trying to use Twig to process an ungainly XML file as a stream of descrete parts. I am using ActivePerl 5.6.1.631 on Win32. I have used variations of the XML tools provided for Perl before for other tasks, but these files are too big for things like XPath, etc. I have loaded the Twig module and am trying to use the twig_roots function, since all I need to do is read data from the tags of interest and then purge the rest of the tree. When I run the code below I get this error message: "Undefined subroutine &main:: called at C:/Perl/site/lib/XML/Parser/Expat.pm line 439." In Expat.pm I see the following (lines 412 through 448): 
sub parse {
  my $self = shift;
  my $arg = shift;
  croak "Parse already in progress (Expat)" if $self->{Used};
  $self->{Used} = 1;
  my $parser = $self->{Parser};
  my $ioref;
  my $result = 0;
  
  if (defined $arg) {
    if (ref($arg) and UNIVERSAL::isa($arg, 'IO::Handler')) {
      $ioref = $arg;
    } else {
      eval {
        no strict 'refs';
    $ioref = *{$arg}{IO};
      };
    }
  }
  
  if (defined($ioref)) {
    my $delim = $self->{Stream_Delimiter};
    my $prev_rs;
    
    $prev_rs = ref($ioref)->input_record_separator("\n$delim\n")
      if defined($delim);
    
    $result = ParseStream($parser, $ioref, $delim);  ### Line 439
        
    ref($ioref)->input_record_separator($prev_rs)
      if defined($delim);
  } else {
    $result = ParseString($parser, $arg);
  }
  
  $result or croak $self->{ErrorMessage};
}

[download]
The only thing I can think is that ParseStream is undefined. A quick search through the Expat, Parser, and Twig modules reveals no other instance of "ParseStream." What could be going on? I have used PPM to "verify --force update" all relevant modules, but to no avail. Here is a snippet of my code: 
#!C:/Perl

use XML::Parser;
use XML::Parser::Expat;
use XML::Twig;

my $t = XML::Twig->new( 
   twig_roots => { 
   '/invoice/header/accountnumber' => \&print_elt_text 
   } );
   
$t->parsefile('MyHugeXML.xml');

sub print_elt_text { 
     my( $t, $elt ) = @_;
     print $elt->text;
     $t->purge;
   }

[download]
Thank you wise ones. Your wisdom is like ambrosia.

In reply to XML-Twig by Anonymous Monk

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