(motive : ByteArray.utf8DecodeChar?.FirstByte → Sort u_1) →
  (x : ByteArray.utf8DecodeChar?.FirstByte) →
    (Unit → motive ByteArray.utf8DecodeChar?.FirstByte.invalid) →
      (Unit → motive ByteArray.utf8DecodeChar?.FirstByte.done) →
        (Unit → motive ByteArray.utf8DecodeChar?.FirstByte.oneMore) →
          (Unit → motive ByteArray.utf8DecodeChar?.FirstByte.twoMore) →
            (Unit → motive ByteArray.utf8DecodeChar?.FirstByte.threeMore) → motive x