}
    }

    // "002F" or "0000..002C"
    val sourceCodePoint0 = readHexadecimalUnsignedLong()
    val sourceCodePoint1 =
      when (select(optionsDot)) {
        DELIMITER_DOT -> {
          if (readByte() != '.'.code.toByte()) throw IOException("expected '..'")
          readHexadecimalUnsignedLong()
        }

        else -> {
          sourceCodePoint0
        }
      }