http://www.perlmonks.org?node_id=1102984

szabgab has asked for the wisdom of the Perl Monks concerning the following question: 

use 5.010;

use HTML::TreeBuilder::XPath;
my $tree= HTML::TreeBuilder::XPath->new;

my $html = <<'HTML';
<html>
<title>four</title>
  <head>
   <title>one</title>
  </head>
  <body>
  <title>two</title>
  </body>
<title>three</title>
</html>
HTML

$tree->parse($html);
say $tree->findvalue( '/html/head/title');

[download]
I was expecting this to print 'one', but instead it printed 'fouronetwothree'. Am I misunderstand what XPath is supposed to do?

Should I use some other module?

Replies are listed 'Best First'.
Re: HTML::TreeBuilder::XPath returns things I don't need?
by choroba (Cardinal) on Oct 06, 2014 at 15:38 UTC
    The <title> tag is valid in the <head> only in HTML. The parser tries to fix the misplaced titles for you, try dumping $tree to see how.
    لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
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[select]
      I see. I tried it inside the body with elements in different locations and it worked as I expected. Thanks.
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Re: HTML::TreeBuilder::XPath returns things I don't need?
by toolic (Bishop) on Oct 06, 2014 at 15:46 UTC
    XML::Twig (by the same module author) can give you what you want: 
    use warnings;
use strict;
use XML::Twig;

my $xml = <<XML;
<html>
<title>four</title>
  <head>
   <title>one</title>
  </head>
  <body>
  <title>two</title>
  </body>
<title>three</title>
</html>
XML

my $twig = XML::Twig->new(
    twig_handlers => { 'html/head/title' => sub { print $_->text(), "\
+n" } },
);
$twig->parse($xml);

__END__

one

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      Thanks
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Re: HTML::TreeBuilder::XPath returns things I don't need?
by Anonymous Monk on Oct 06, 2014 at 23:20 UTC

    Am I misunderstand what XPath is supposed to do?

    Trees are trees :)

    htmltreexpather.pl 

    $ perl htmltreexpather.pl junktitle.html _tag title
HTML::Element=HASH(0xcded54)    0.0.0
four
/html/head/title
/html/head/title
/html/head/title
------------------------------------------------------------------
HTML::Element=HASH(0xcdea04)    0.0.1
one
/html/head/title[2]
/html/head/title[2]
/html/head/title[2]
------------------------------------------------------------------
HTML::Element=HASH(0xcde954)    0.0.2
two
/html/head/title[3]
/html/head/title[3]
/html/head/title[3]
------------------------------------------------------------------
HTML::Element=HASH(0xcde8e4)    0.0.3
three
/html/head/title[4]
/html/head/title[4]
/html/head/title[4]
------------------------------------------------------------------
##################################################################

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