anchor.diff:  -export([internal_function/1]).
   -export([rev_deps/1, rev_mod_deps/1]).
   -export([collect_dependencies/1, is_concrete_fun/1, is_primop/1]).
  --export([rev_append/2, dict_cons/3]).
  +-export([dict_cons/3]).
   
   -export([remove_args/1]).
   -export([count/1]).
  
positive.code:     true;
  is_special(_) ->
      false.
  
  %% Should be more efficient than append, when order is not important.
  
  -spec rev_append([term()], [term()]) -> [term()].
  
  rev_append([], L) ->
      L;
  rev_append([H|T], L) ->
      rev_append(T, [H|L]).
  
  
  %% Faster than dict:append, in case order is not important.
  
negative.code:     Key = {count, Name},
      case get(Key) of
          undefined ->
              put(Key, 2),
              1;
          N when is_integer(N) ->
              put(Key, N + 1)
  