docs: public Bits readAhead(final int bytes) throws IOException {
      assert (0 < bytes);
      if (0 < bytes) {
        final byte[] buffer = new byte[bytes];
        int bytesRead = this.inner.read(buffer);
        if (bytesRead > 0) {
          this.remainder = this.remainder.concatenate(new Bits(Arrays.copyOf(buffer, bytesRead)));
        }
      }
      return this.remainder;
    }