anchor.diff:  	false -> [Test|kill_seen_1(T, Dst)]
       end;
   kill_seen_1([], _) -> [].
  -
  -	    
  
positive.code: 		false ->
  		    %% Remember that we have seen this test.
  		    SeenTests = gb_sets:insert(Test, SeenTests0),
  		    make_select_val(I, Is, SeenTests, Acc)
  	    end
      end;
  peep([{select_val,Src,Fail,
  
negative.code:     peep(Is, gb_sets:empty(), [I|Acc]);
  peep([], _, Acc) -> reverse(Acc).
  
  kill_seen(Dst, Seen0) ->
      gb_sets:from_ordset(kill_seen_1(gb_sets:to_list(Seen0), Dst)).
  
  