anchor.diff:  
   safe_fetch(Key, D, Def) ->
       case find(Key, D) of
  -    {ok,Val} -> Val;
  -    error -> Def
  +        {ok,Val} -> Val;
  +        error -> Def
       end.
  
positive.code:     %% Sneaky! m-l args a list of patterns so wrap with list and pass
      %% in as one pattern. Have already checked a proper list.
      foreach_form(fun ([As|B], S) -> check_clause([[list|As]|B], Env, L, S) end,
           'match-lambda', L, St, Cls).
  
  %% check_ml_clauses(Cls, Env, L, St) ->
  %%     %% Sneaky! m-l args list of patterns so just pass in as one pattern.
  
negative.code:     Predefs1 = [{new,[lambda,Ps,[quote,dummy]],1}|Predefs0],
      Exps1 = add_element({new,Ar}, Exps0),
      case St#lint.extd of
          [] ->
              {Ps,[{instance,[lambda,Ps,[quote,dummy]],1}|Predefs1],
               add_element({instance,Ar},Exps1)};
          _ ->
              {[base|Ps],[{instance,[lambda,[base|Ps],[quote,dummy]],1}|Predefs1],
               add_element({instance,Ar+1},Exps1)}
      end.
  
  check_exports(all, _, St) -> St;                %All is all
  check_exports(Exps, Fs, St) ->
      foldl(fun (E, S) ->
                    case is_element(E, Fs) of
                        true -> S;
                        false -> add_error(9999, {unbound_func,E}, S)
                    end
            end, St, Exps).
  
  %% add_exports(Old, More) -> New.
  
  