anchor.diff:  
   
   -ifdef(TEST).
  --dialyzer({no_match, dlist_test_/0}).
   dlist_test_() ->
       {"deep list traversal",
        [{"non-list term -> singleton list",
  
positive.code: uniq([]) -> [].
  
  -ifdef(TEST).
  -dialyzer({[no_match, no_fail_call, no_improper_lists], uniq_test_/0}).
  uniq_test_() ->
      {"uniq",
       [?_assertError(function_clause, uniq(ok)),
  
negative.code: is_nonempty_string(Cs) -> is_string(Cs).
  
  -ifdef(TEST).
  is_string_test_() ->
      {"is_string",
       [{"no non-lists", ?_assert(not is_string($A))},
  