anchor.diff:  
   check_fbindings(Fbs0, St0) ->
       AddFb = fun(F, Fs, L, St) ->
  -            case member(F, Fs) of
  -            true -> {Fs,add_error(L, {redef_fun,F}, St)};
  -            false -> {add_element(F, Fs),St}
  -            end
  -        end,
  +                    case member(F, Fs) of
  +                        true -> {Fs,add_error(L, {redef_fun,F}, St)};
  +                        false -> {add_element(F, Fs),St}
  +                    end
  +            end,
       Check = fun ({V,[lambda,Args|_],L}, {Fs,St}) ->
  -            case is_symb_list(Args) of
  -            true -> AddFb({V,length(Args)}, Fs, L, St);
  -            false -> {Fs,bad_form_error(L, lambda, St)}
  -            end;
  -        ({V,['match-lambda',[Pats|_]|_],L}, {Fs,St}) ->
  -            case is_proper_list(Pats) of
  -            true -> AddFb({V,length(Pats)}, Fs, L, St);
  -            false -> {Fs,bad_form_error(L, 'match-lambda', St)}
  -            end;
  -        (_, Acc) -> Acc            %Error here flagged later
  -        end,
  +                    case is_symb_list(Args) of
  +                        true -> AddFb({V,length(Args)}, Fs, L, St);
  +                        false -> {Fs,bad_form_error(L, lambda, St)}
  +                    end;
  +                ({V,['match-lambda',[Pats|_]|_],L}, {Fs,St}) ->
  +                    case is_proper_list(Pats) of
  +                        true -> AddFb({V,length(Pats)}, Fs, L, St);
  +                        false -> {Fs,bad_form_error(L, 'match-lambda', St)}
  +                    end;
  +                (_, Acc) -> Acc                 %Error here flagged later
  +            end,
       foldl(Check, {[],St0}, Fbs0).
   
   %% check_if(IfBody, Env, Line, State) -> State.
  
positive.code: 
  safe_fetch(Key, D, Def) ->
      case find(Key, D) of
      {ok,Val} -> Val;
      error -> Def
      end.
  
negative.code:     lfe_io:format1("multiple variable: ~w", [S]);
  format_error({redef_fun,F}) ->
      lfe_io:format1("redefining function: ~w", [F]);
  format_error(illegal_literal) -> "illegal literal";
  format_error(illegal_pattern) -> "illegal pattern";
  format_error(illegal_guard) -> "illegal guard";
  format_error(illegal_bitseg) -> "illegal bit segment";
  