The look_down method is not finding the DOCTYPE declaration although it is present in Data::Dumpers output as described in the docs. What's the best way to do this? 
#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;
$Data::Dumper::Indent = 1;
$Data::Dumper::Sortkeys = 1;

use HTML::TreeBuilder;

my $content = do{local $/;<DATA>};
my $root = HTML::TreeBuilder->new_from_content($content);

print $root->tag, qq{\n}; 
# prints: html
print $root->{_decl}{_tag}, qq{\n}; 
# prints: ~declaration
print $root->{_decl}{text}, qq{\n}; 
# prints: DOCTYPE html PUBLIC "XHTML"

my $dec = $root->look_down(
  _tag  => q{~declaration},
) or die qq{declaration not found\n};


$dec->splice_content(
  0, 
  1, 
  q{<!DOCTYPE html PUBLIC "HTML4">},
) or die qq{splice failed\n};

print $root->as_HTML;

__DATA__
<!DOCTYPE html PUBLIC "XHTML">
<html>
<head><title>declaration</title></head>
<body><p>declaration</p></body>
</html>

[download]
extract from Data::Dumper output 
  '_decl' => bless( {
    '_tag' => '~declaration',
    'text' => 'DOCTYPE html PUBLIC "XHTML"'
  }, 'HTML::Element' ),

[download]

In reply to Using HTML::TreeBuilder to change the DOCTYPE declaration by wfsp

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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