docs: private Object getAndTick(Keep keep, BitReader bitreader)
              throws JSONException {
          try {
              int width = keep.bitsize();
              int integer = bitreader.read(width);
              Object value = keep.value(integer);
              if (JSONzip.probe) {
                  JSONzip.log("\"" + value + "\"");
                  JSONzip.log(integer, width);
              }
              if (integer >= keep.length) {
                  throw new JSONException("Deep error.");
              }
              keep.tick(integer);
              return value;
          } catch (Throwable e) {
              throw new JSONException(e);
          }
      }