anchor.diff:  unpack(Maybe_Options) ->
       [Options, Maybe_Messages] = unpack(Maybe_Options, orddict:new()),
       Dict_Options = orddict:store(options, Options, orddict:new()),
  -    {ok, Dict_Options, Maybe_Messages}.
  +    {ok, {ppspp_options, Dict_Options}, Maybe_Messages}.
   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   unpack( <<?PPSPP_SUPPORTED_VERSION,
             Version:?BYTE,
  
positive.code: defaults_test() ->
      Hash ="c89800bfc82ed01ed6e3bfd5408c51274491f7d4",
      Root_Hash = convert:hex_string_to_padded_binary(Hash),
      Expected_Defaults = [{chunk_addressing_method,chunking_32bit_chunks},
                           {chunk_size,1024},
                           {content_integrity_check_method,merkle_hash_tree},
                           {merkle_hash_tree_function,sha},
                           {minimum_version,1},
                           {swarm_id, Root_Hash},
                           {version,1}],
      [?_assertEqual( Expected_Defaults , use_default_options(Root_Hash) )].
  -endif.
  
  
negative.code:               ppspp_option/0]).
  
  -opaque root_hash() :: binary().
  -opaque ppspp_options() :: {ppspp_options, list({ ppspp_option(), any()})}.
  -type ppspp_option() :: supported_version
  | minimum_version
  | swarm_id
  