anchor.diff:  from_list(_) -> erlang:nif_error(undef).
   
   
  +%% Shadowed by erl_bif_types: maps:is_key/2
   -spec is_key(Key,Map) -> boolean() when
       Key :: term(),
       Map :: map().
  
positive.code: to_list(_) -> erlang:nif_error(undef).
  
  
  -spec update(Key,Value,Map1) -> Map2 when
      Key :: term(),
      Value :: term(),
  
negative.code:          new/0, put/3, remove/2, take/2,
           to_list/1, update/3, values/1]).
  
  %% Shadowed by erl_bif_types: maps:get/2
  -spec get(Key,Map) -> Value when
      Key :: term(),
      Map :: map(),
  