Update: Saw GrandFather's reply. There is some misunderstanding. I guess that that was my fault, and I could have expressed myself more clearly. I have never doubted the merit of his code. The intention of this reply was/is not about whether his orginal HTML was valid. What I am saying is that, as_html converts a valid document to an invalid document, and that is a bug. To prove that, I needed a valid HTML document (in a more strict sense) that can pass the validation service, and that's all why I modified the original code. Otherwise, both HTML's before and after convertion fail the validation, and I cannot prove my point. No worries, GrandFather ;-)

=========================================

This is a bug, by HTML 4.01 specification. You do not need to be familiar with the specification, we can use W3C validate service to verify those HTML documents in this reply.

I modified your code a little bit to contain a valid HTML document. The HTML document passed W3C validation as tentatively valid.

use strict;
use warnings;
use HTML::TreeBuilder;

my $data = do {local $/ = ""; <DATA>};

my $tree = HTML::TreeBuilder->new;
$tree->store_comments(1);
$tree->store_declarations(1);
$tree->parse ($data);
$tree->eof ();

print $tree->as_HTML();


__DATA__
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
   "http://www.w3.org/TR/html4/strict.dtd">
<HTML>
   <HEAD>
      <TITLE>My first HTML document</TITLE>
   </HEAD>
   <BODY>
      <P>Hello world!
   </BODY>
</HTML>

[download]

Run this program it generates:

<html><head><title>My first HTML document</title></head><body><p>Hello
+ world! </body><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
   "http://www.w3.org/TR/html4/strict.dtd"></html>

[download]

And this generated HTML does not pass the validate service. It complains that DOCTYPE cannot be found and is misplaced.

In reply to Re: HTML::TreeBuilder bug or feature? by pg
in thread HTML::TreeBuilder bug or feature? by GrandFather

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