*
 * This implementation's STD3 rules are configured to `UseSTD3ASCIIRules=false`. This is
 * permissive and permits the `_` character.
 *
 * [mapping table]: https://www.unicode.org/reports/tr46/#IDNA_Mapping_Table
 * [mapping step]: https://www.unicode.org/reports/tr46/#ProcessingStepMap
 */
class SimpleIdnaMappingTable internal constructor(
  internal val mappings: List<Mapping>,
) {
  /**

 *
 * [RFC 3492]: https://datatracker.ietf.org/doc/html/rfc3492
 * [RFC 5890]: https://datatracker.ietf.org/doc/html/rfc5890
 * [UTS #46]: https://www.unicode.org/reports/tr46/
 */
object Punycode {
  val PREFIX_STRING = "xn--"
  val PREFIX = PREFIX_STRING.encodeUtf8()

  private const val BASE = 36
  private const val TMIN = 1
  private const val TMAX = 26

    fun retry(): Plan?
  }

  /**
   * What to do once a plan has executed.
   *
   * If [nextPlan] is not-null, another attempt should be made by following it. If [throwable] is
   * non-null, it should be reported to the user should all further attempts fail.
   *
   * The two values are independent: results can contain both (recoverable error), neither