"XML::Twig" is implictly recursive. You don't really need to do any more recursion. But I also don't think you're doing anything anywhere near as complicated as that: 

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

use XML::Twig;
use Data::Dumper;

sub print_book {
    my ( $twig, $book ) = @_; 
    my %this_book = map { $_ -> tag, $_ -> text } $book -> children;
    print Dumper \%this_book;
    
    $twig -> purge; 
}

my $twig = XML::Twig -> new ( 'twig_handlers' =>
                                 { 'Book' => \&print_book } );
   $twig ->  parsefile ( 'your_xml_file' );

[download]

This runs through your your XML; and turns each `Book` into a hash. (And then Dumps it, but you can do something more useful). Or have I missed something profound about what you're trying to accomplish? Output from the above looks a bit like: 

$VAR1 = {
          'Title' => 'The age of rocks',
          'Author' => 'Mary',
          'Released' => '8/16/1944'
        };

[download]

Alternatively, you can simply use the "_all_" handler, and test each node for having children:

sub handle_node { 
    my ( $twig, $element ) = @_;
    unless ( $element -> has_children ) { 
        print "(", $element -> parent -> tag, ") ", 
                   $element -> tag, ": ", $element -> text,"\n";
    }
    $twig -> purge; 
}

my $twig = XML::Twig -> new ( 'twig_handlers' => 
                                { '_all_' => \&handle_node } );
   $twig  ->  parsefile ( 'yourfile');

[download]

This will traverse all the nodes, printing any that don't have children, and purging to free up memory. With your sample data, this prints:

(Book) Title: The book of books
(Book) Author: Sally
(Book) Released: 1/2/2008
(Book) Title: The page of pages
(Book) Author: Amanda
(Book) Released: 6/3/1998
(Book) Title: The book of pages
(Book) Author: John
(Book) Released: 6/22/1963
(Book) Title: The rock of ages
(Book) Author: Frank
(Book) Released: 5/21/2004
(Book) Title: The age of rocks
(Book) Author: Mary
(Book) Released: 8/16/1944

[download]

In reply to Re: Is it possible to parse an XML file recursively using XML::Twig? by Preceptor
in thread Is it possible to parse an XML file recursively using XML::Twig? by Ppeoc

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