From the docs: 
       $p->get_token
           This method will return the next token found in the HTML do
+cument, or "undef" at the
           end of the document.  The token is returned as an array ref
+erence.  The first element
           of the array will be a string denoting the type of this tok
+en: "S" for start tag, "E"
           for end tag, "T" for text, "C" for comment, "D" for declara
+tion, and "PI" for process
           instructions.  The rest of the token array depend on the ty
+pe like this:

             ["S",  $tag, $attr, $attrseq, $text]
             ["E",  $tag, $text]
             ["T",  $text, $is_data]
             ["C",  $text]
             ["D",  $text]
             ["PI", $token0, $text]

[download]

It appears you're trying to read the href attribute from a token without attributes (like an end tag or a text). Also not all html tags actually have an href attribute, which should give warnings if you've enabled them.

How about (untested): 

while (my $token = $stream -> get_token()){
   if ($token->[0] eq 'S') { # start tag
     if (exists $token->[2]->{href}) { # tag has href attribute
        print "PDF link!\n" if $token -> [2] -> {'href'} =~  m/\.pdf/;
     }
   }
}

[download]

updated:

Your code "works" without strict because using $something->{href}, where $something is a string will reference a global hash named $something, creating it if it doesn't exist yet (i.e. if $something eq 'blah', a global hash %blah will be created if it doesn't already exists). This can cause all kinds of mayhem and is a good reason to always use strict (see strict 'refs' in the strict documentation and symbolic links in perlref)

updated: moved doc links to cpan.org, perldoc.com is messing up again.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: use strict and TokeParser by Joost
in thread use strict and TokeParser by young_stu

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