anchor.diff:  
   literal_value({_TokenType, _Line, Value}) -> Value.
   
  +%% Make relative names absolute.  The parser produces names as atoms,
  +%% such as m1, or as a list of path components separated by the
  +%% dot-atom, '.', such as [m1,'.',m2].  Such names are relative.
  +%% An absolute name is a name that begins with a dot-atom, for example
  +%% ['.',m1] or ['.',m1,'.',m2], much like the slash or backslash character
  +%% in a file system path.
  +%%
  +%% The resulting names will begin with package names if the
  +%% `use_package' option is specified, and also if the proto
  +%% file define a package.
  +%%
  +%% Currently, a sort-of name-resolution step is built-in: relative
  +%% names that refer to nested definitions, at the same level or more
  +%% deeply nested, are turned into absolute names, too.
  +%%
  +%% Prerequisites: No prerequisite, a data structure from the parser is ok.
   absolutify_names(Defs) ->
     absolutify_names(Defs, []).
   absolutify_names(Defs, Opts) ->
  
positive.code:                     FieldsOrDefs),
      {lists:reverse(RFields2), Defs2}.
  
  
  
  %% `Defs' is expected to be flattened and may or may not be reformatted
  verify_defs(Defs) ->
      collect_errors(Defs,
                     [{msg,     [fun verify_msg/2, fun verify_field_defaults/2]},
  
negative.code:       end,
        RPCs).
  
  %% For nested message definitions such as
  %% ```
  %%    message m1 {
  %%      required uint32 f1 = 1;
  %%      message m2 { ... }
  %%      enum e2 { ... }
  %%    };",
  %% '''
  %% the parser will produce a nested structure, such as:
  %% ```
  %%   [{{msg,M1},[#field{},
  %%               {{msg,M2}, [...]},
  %%               {{enum,E2}, [...]}]}]
  %% '''
  %% Flattenning means to lift the nested m2 and e2 definition to the top-level,
  %% so the above turns into:
  %% ```
  %%   [{{msg,M1},[#field{}]},
  %%    {{msg,M2}, [...]},
  %%    {{enum,E2}, [...]}]
  %% '''
  %%
  %% Prerequisites:
  %% `Defs' is expected to be absolutified
  flatten_defs(Defs) ->
      lists:reverse(
  