anchor.diff:  -define(TYPER_ANN_DIR, "typer_ann").
   
   -type line()      :: non_neg_integer().
  +-type fa()        :: {atom(), arity()}.
   -type func_info() :: {line(), atom(), arity()}.
   
   -record(info, {records = map__new() :: map(),
  
positive.code: 
  %%--------------------------------------------------------------------
  %% A convenient abstraction of a Key-Value mapping data structure
  %%--------------------------------------------------------------------
  
  -type map() :: dict().
  
negative.code: map__lookup(Key, Map) ->
    try dict:fetch(Key, Map) catch error:_ -> none end.
  
  -spec map__from_list([{fa(), term()}]) -> map().
  map__from_list(List) ->
    dict:from_list(List).
  
  