anchor.diff:           count/1,
            fold_idx/3
           ]).
  +
   -export_type([mfile/0, fold_fun/0]).
   
   -include_lib("mmath/include/mmath.hrl").
  
positive.code: %%%-------------------------------------------------------------------
  %%% @author Heinz N. Gies <heinz@licenser.net>
  %%% @copyright (C) 2016, Heinz N. Gies
  %%% @doc MStore file module. 
  %%%
  %%% @end
  %%% Created :  5 Dec 2016 by Heinz N. Gies <heinz@licenser.net>
  
negative.code:             end
      end.
  
  -spec metrics(mfile()) ->
                      btrie:btrie().
  metrics(#mfile{index = Index}) ->
      Index.
  %%--------------------------------------------------------------------
  %% @doc
  