HTML::TokeParser comes with HTML::Parser, HTML::Element with HTML::Tree.

The problem is if there is no such html::tokeparser in my perl, I should get the "can't locate ...@INC" error. Not the perl interpreter error.

You're right. That does indeed imply there's a lot more wrong than just a missing module. Do you have, by any chance, more than one perl installed? An older version, 5.6.x or earlier?

I looked in to perl/lib/html directory. Tokerparser was there with some other modules.

Try

perl -le "print for @INC"
[download]

and see if the modules you can find are under one of the directories listed there, or if it's using modules of another version of Perl.