Scanning HTML

Screen scraping with HTML::TreeBuilder:

my $real_h1 = $tree->look_down(
    '_tag', 'h1',
    sub {
        my $link = $_[0]->look_down('_tag','a');
        return 1 unless $link; # no link means it's fine
        return 0 if $link->attr('href') =~ m{/dyna/}; # a link to there is bad
        return 1; # otherwise okay
    }
);