anchor.diff:  tag({<<"link">>, As, _}, MD, P) ->
       Name = z_string:to_lower(proplists:get_value(<<"rel">>, As)),
       Content = proplists:get_value(<<"href">>, As),
  -    {meta_link(Name, Content, MD), P};
  +    {meta_link(Name, Content, As, MD), P};
   tag({<<"img">>, As, _}, MD, P) ->
       case proplists:get_value(<<"src">>, As, <<>>) of
           <<>> -> 
  
positive.code: meta_tag(<<"content-type">>, Content, MD) -> [{content_type, Content}|MD];
  meta_tag(_Name, _Content, MD) -> MD.
  
  meta_link(<<"canonical">>, Content, MD) -> [{canonical_url, Content}|MD];
  meta_link(<<"shortlink">>, Content, MD) -> [{short_url, Content}|MD];
  meta_link(<<"shorturl">>, Content, MD) -> [{short_url, Content}|MD];
  meta_link(<<"icon">>, Content, MD) -> [{icon_fav, Content}|MD];
  meta_link(<<"shortcut icon">>, Content, MD) -> [{icon_shortcut, Content}|MD];
  meta_link(<<"apple-touch-icon">>, Content, MD) -> [{icon_touch, Content}|MD];
  meta_link(_Name, _Content, MD) -> MD.
  
  split_class(undefined) -> [];
  split_class(Class) -> binary:split(Class, <<" ">>, [global]).
  
negative.code: p1([P|Ps], MD) ->
      case z_string:trim(proplists:get_value(P, MD#url_metadata.metadata,<<>>)) of
          <<>> -> p1(Ps, MD);
          Value -> maybe_abs_link(is_link_property(P), Value, MD#url_metadata.final_url)
      end.
  
  maybe_abs_link(false, Value, _FinalUrl) ->
      Value;
  maybe_abs_link(true, <<>>, _FinalUrl) ->
      undefined;
  maybe_abs_link(true, undefined, _FinalUrl) ->
      undefined;
  maybe_abs_link(true, Value, FinalUrl) ->
      z_url:abs_link(Value, FinalUrl).
  
  is_link_property(canonical_url) -> true;
  is_link_property(short_url) -> true;
  is_link_property(image_nav) -> true;
  is_link_property(image) -> true;
  is_link_property(icon_nav) -> true;
  is_link_property(icon_shortcut) -> true;
  is_link_property(_) -> false.
  
  
  content_disp_filename(undefined) ->
      undefined;
  