anchor.diff:  
   %% These work on list of forms in "file format".
   -export([expand_forms/2,expand_forms/3,macro_forms/2,macro_forms/3]).
  --export([macro_form_init/1,macro_form/4,macro_fileform/3]).
  --export([expand_form_init/1,expand_form/4,expand_fileform/3]).
  +-export([macro_form_init/0,macro_form_init/1,macro_form/4,macro_fileform/3]).
  +-export([expand_form_init/0,expand_form_init/1,
  +         expand_form/4,expand_fileform/3]).
   
   -export([format_error/1]).
   
  
positive.code:     {F1,E1,St1} = pass_form(F0, E0, St0#mac{line=L}),
      return_status({F1,L}, E1, St1).
  
  %% macro_form_init(CompInfo) -> State.
  %% macro_form(Form, Line, Env, State) -> {Form,Env,State}.
  %% macro_fileform(Form, Env, State) -> {FileForm,Env,State}.
  %%  Collect macro definitions in a (file)form, expand top-level macros
  %%  and keep all forms.
  
  macro_form_init(Ci) ->
      default_state(Ci, false, true).
  
negative.code: default_state(#cinfo{file=File,opts=Os,ipath=Is}, Expand, Keep) ->
      #mac{expand=Expand,keep=Keep,line=1,file=File,opts=Os,ipath=Is}.
  
  %% expand_form_init() -> State.
  %% expand_form_init(CompInfo) -> State.
  %% expand_form(Form, Line, Env, State) -> {Form,Env,State}.
  %% expand_fileform(Form, Env, State) -> {Form,Env,State}.
  %%  Collect macro definitions in a (file)form, completely expand all
  %%  macros and only keep all functions.
  
  expand_form_init() ->
      default_state(true, false).
  
  expand_form_init(Ci) ->
      default_state(Ci, true, false).
  
  