Hello Monks,

I'm looking to replicate the example that cpan gave me for HTML::TreeBuilder and fall short. I took a look at the yahoo site which I still use to get news and have an internet identity with, one that is useful, so I don't feel like I ever want yahoo to disappear.

Q1) The first thing I ask for is a diagnosis for the errors I post after its source. https://metacpan.org/pod/HTML::Tree::Scanning

use strict;
use HTML::TreeBuilder 2.97;
use LWP::UserAgent;
sub get_headlines {
  my $url = $_[0] || die "What URL?";
   
  my $response = LWP::UserAgent->new->request(
    HTTP::Request->new( GET => $url )
  );
  unless($response->is_success) {
    warn "Couldn't get $url: ", $response->status_line, "\n";
    return;
  }
   
  my $tree = HTML::TreeBuilder->new();
  $tree->parse($response->content);
  $tree->eof;
   
  my @out;
  foreach my $link (
    $tree->look_down(   # !
      '_tag', 'a',
      sub {
        return unless $_[0]->attr('href');
        my @c = $_[0]->content_list;
        @c == 1 and ref $c[0] and $c[0]->tag eq 'b';
      }
    )
  ) {
    push @out, [ $link->attr('href'), $link->as_text ];
  }
   
  warn "Odd, fewer than 6 stories in $url!" if @out < 6;
  $tree->delete;
  return @out;
}

foreach my $section (qw[tc sc hl wl en]) {
  my @links = get_headlines(
    "http://dailynews.yahoo.com/h/$section/"
  );
  print
    $section, ": ", scalar(@links), " stories\n",
    map(("  ", $_->[0], " : ", $_->[1], "\n"), @links),
    "\n";
}

[download]

The terminal looks like it's looking for urls that no longer exist:

C:\cygwin64\home\Fred\pages2\hunt>perl lib2.pl
Couldn't get http://dailynews.yahoo.com/h/tc/: 500 Can't connect to da
+ilynews.ya
hoo.com:80 (Bad hostname)
tc: 0 stories

Couldn't get http://dailynews.yahoo.com/h/sc/: 500 Can't connect to da
+ilynews.ya
hoo.com:80 (Bad hostname)
sc: 0 stories

Couldn't get http://dailynews.yahoo.com/h/hl/: 500 Can't connect to da
+ilynews.ya
hoo.com:80 (Bad hostname)
hl: 0 stories

Couldn't get http://dailynews.yahoo.com/h/wl/: 500 Can't connect to da
+ilynews.ya
hoo.com:80 (Bad hostname)
wl: 0 stories

Couldn't get http://dailynews.yahoo.com/h/en/: 500 Can't connect to da
+ilynews.ya
hoo.com:80 (Bad hostname)
en: 0 stories

[download]

Q3) My next question goes to syntax. What is this creature: $_->[0]

Q4) What is a clean, contemporary update for this example?

Thank you for your comment,

In reply to using HTML::TreeBuilder effectively by Aldebaran

Title:
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