I'm sure I'm missing some interaction between the various options, but I was wondering if someone (mirod?) could tell me how to accomplish the following. I have an XML document that I want to process with XML::Twig. I want the output document to retain the formatting characteristics of the input document. I also want to use twig_roots, since the file will not fit into memory, and is record-based. (i.e. the processing of each record is self-contained.). I used twig_print_outside_roots, because I want to specify a filehandle for the default prints/flushes. (Is there something more appropriate for that purpose?) The problem is that the root (wrapper) element's start tag is being output twice.

Example input:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE foo SYSTEM "/path">
<foo version="blah">
<record>stuff</record>
<record>stuff 2</record>
</foo>

[download]

Desired output:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE foo SYSTEM "/path">
<foo version="blah">
<record>altered stuff</record>
<record>altered stuff 2</record>
</foo>

[download]

My attempt:

#!/usr/bin/perl
use strict;
use warnings;
use XML::Twig;
open my $outfh, '>', "out.xml" or die ">out.xml:$!";
my $p = XML::Twig->new(
    twig_print_outside_roots => $outfh,
    twig_roots => {
        record => sub {
            $_->set_text("altered ".$_->text);
            shift->flush
        }
    },
    empty_tags => 'html',
    keep_encoding => 1,
    keep_spaces => 1,
);
$p->parsefile("in.xml");
print "DONE\n";

[download]

Actual output:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE foo SYSTEM "/path">
<foo version="blah">
<foo version="blah"><record>altered stuff</record> # the extra <foo ve
+rsion="blah"> is the problem.
<record>altered stuff 2</record>
</foo>

[download]

In reply to XML::Twig outputting root element start tag twice by benizi

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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