# remember that HTML::TreeBuilder inherits from HTML::Element.
  sub HTML::Element::strip_elements
  {
    my( $e, $tag ) = @_;
    $_->replace_with_content for $e->find_by_tag_name($tag);
    $e
  }

  # now we can write our subroutine like this:
  sub strip_a_elements
  {
    HTML::TreeBuilder
    ->new_from_content( $_[0] )
    ->strip_elements('a')
    ->as_HTML
  }

  # and call it:
  my $html_minus_links = strip_a_elements( $html );