Can't call method "text" on an undefined value at IDOCXML_parse2.pl line 27, <$list> line 1.
 at IDOCXML_parse2.pl line 23
 at IDOCXML_parse2.pl line 23

##</code><code>##

#!/usr/bin/perl
use warnings;
use strict;

use Text::CSV_XS;
use XML::Twig;

my $listfile = shift;
open my $list, '<', $listfile or die $!;
while (my $xmlfile = <$list>) {
    chomp $xmlfile;

my $twig = XML::Twig->new(
    twig_handlers => {
        'EDI_DC40' => \&process_EDI_DC40,
        },
    );

my $csv = Text::CSV_XS->new({
'sep_char'    => "|",
});

$twig->parsefile($xmlfile);
sub process_EDI_DC40 {
    my( $twig, $thingy ) = @_;

    my @values = map { $thingy->first_child( $_ )->text }
        qw(DOCNUM MESTYP SNDPRN RCVPOR RCVPRN);

    $csv->say( *STDOUT, \@values );
    }

}