anchor.diff:  
   'subst-if'(New, Test, Tree) ->
       case Test(Tree) of
  -    true -> New;
  -    false ->
  -        case Tree of
  -        [H|T] ->
  -            ['subst-if'(New, Test, H)|'subst-if'(New, Test, T)];
  -        _ -> Tree
  -        end
  +        true -> New;
  +        false ->
  +            case Tree of
  +                [H|T] ->
  +                    ['subst-if'(New, Test, H)|'subst-if'(New, Test, T)];
  +                _ -> Tree
  +            end
       end.
   
   %% subst-if-not(New, Test, Tree) -> Tree.
   
   'subst-if-not'(New, Test, Tree) ->
       case Test(Tree) of
  -    false -> New;
  -    true ->
  -        case Tree of
  -        [H|T] ->
  -            ['subst-if-not'(New, Test, H)|'subst-if-not'(New, Test, T)];
  -        _ -> Tree
  -        end
  +        false -> New;
  +        true ->
  +            case Tree of
  +                [H|T] ->
  +                    ['subst-if-not'(New, Test, H)|'subst-if-not'(New, Test, T)];
  +                _ -> Tree
  +            end
       end.
   
   %% sublis(AList, Tree) -> Tree.
   
   sublis(Alist, Tree) ->
       case assoc(Tree, Alist) of
  -    [_|New] -> New;                         %Found it
  -    [] ->                                   %Not there
  -        case Tree of
  -        [H|T] ->
  -            [sublis(Alist, H)|sublis(Alist, T)];
  -        _ -> Tree
  -        end
  +        [_|New] -> New;                         %Found it
  +        [] ->                                   %Not there
  +            case Tree of
  +                [H|T] ->
  +                    [sublis(Alist, H)|sublis(Alist, T)];
  +                _ -> Tree
  +            end
       end.
   
   eval(Sexpr) -> eval(Sexpr, lfe_env:new()).  %Empty environment.
  
positive.code: 
  'rassoc-if'(Pred, [[_|V]=Pair|L]) ->
      case Pred(V) of
      true -> Pair;
      false -> 'rassoc-if'(Pred, L)
      end;
  'rassoc-if'(_, []) -> [].
  
  'rassoc-if-not'(Pred, [[_|V]=Pair|L]) ->
      case Pred(V) of
      false -> Pair;
      true -> 'rassoc-if-not'(Pred, L)
      end;
  'rassoc-if-not'(_, []) -> [].
  
  
negative.code: %%  exception; SkipFun is used to trim the end of stack; FormatFun is
  %%  used to format terms; and Indentation is the current column.
  
  format_exception(Cl, Error0, St0, Sf, Ff, I) ->
      Cs = case Cl of                         %Class type as string
               throw -> "throw";
               exit -> "exit";
               error -> "error"
           end,
      {Error1,St1} = case is_stacktrace(St0) of
                         true -> {Error0,St0};
                         false -> {{Error0,St0},[]}
                     end,
      P = "exception " ++ Cs ++ ": ",         %Class description string
      [P,lfe_io:prettyprint1(Error1, 10, length(P)+I-1),"\n",
       format_stacktrace(St1, Sf, Ff)].
  
  %% format_stacktrace(Stacktrace, SkipFun, FormatFun) -> DeepCharList.
  %%  Format a stacktrace. SkipFun is used to trim the end of stack;
  