anchor.diff:                          H3),
       "application/x-www-form-urlencoded" = ?MODULE:get_primary_value(
                                                "content-type", H4),
  +    H4 = ?MODULE:delete_any("nonexistent-header", H4),
  +    H3 = ?MODULE:delete_any("content-type", H4),
       ok.
   
   %% @spec empty() -> headers()
  
positive.code:             gb_trees:update(K1, {K0, V2}, T)
      end.
  
  %% Internal API
  
  expand({array, L}) ->
  
negative.code: -module(mochiweb_headers).
  -author('bob@mochimedia.com').
  -export([empty/0, from_list/1, insert/3, enter/3, get_value/2, lookup/2]).
  -export([delete_any/2, get_primary_value/2]).
  -export([default/3, enter_from_list/2, default_from_list/2]).
  -export([to_list/1, make/1]).
  -export([test/0]).
  