@Override
    public String toString() {
      return description;
    }
  }

  /** Implementation of {@link #digit()}. */
  private static final class Digit extends RangesMatcher {
    // Plug the following UnicodeSet pattern into
    // https://unicode.org/cldr/utility/list-unicodeset.jsp
    // [[:Nd:]&[:nv=0:]&[\u0000-\uFFFF]]
    // and get the zeroes from there.

    // Must be in ascending order.

    @Override
    public String toString() {
      return description;
    }
  }

  /** Implementation of {@link #digit()}. */
  private static final class Digit extends RangesMatcher {
    // Plug the following UnicodeSet pattern into
    // https://unicode.org/cldr/utility/list-unicodeset.jsp
    // [[:Nd:]&[:nv=0:]&[\u0000-\uFFFF]]
    // and get the zeroes from there.

    // Must be in ascending order.

{content:"\f67f"}.fa-plane:before{content:"\f072"}.fa-plane-arrival:before{content:"\f5af"}.fa-plane-departure:before{content:"\f5b0"}.fa-play:before{content:"\f04b"}.fa-play-circle:before{content:"\f144"}.fa-playstation:before{content:"\f3df"}.fa-plug:before{content:"\f1e6"}.fa-plus:before{content:"\f067"}.fa-plus-circle:before{content:"\f055"}.fa-plus-square:before{content:"\f0fe"}.fa-podcast:before{content:"\f2ce"}.fa-poll:before{content:"\f681"}.fa-poll-h:before{content:"\f682"}.fa-poo:befor...

{content:"\f67f"}.fa-plane:before{content:"\f072"}.fa-plane-arrival:before{content:"\f5af"}.fa-plane-departure:before{content:"\f5b0"}.fa-play:before{content:"\f04b"}.fa-play-circle:before{content:"\f144"}.fa-playstation:before{content:"\f3df"}.fa-plug:before{content:"\f1e6"}.fa-plus:before{content:"\f067"}.fa-plus-circle:before{content:"\f055"}.fa-plus-square:before{content:"\f0fe"}.fa-podcast:before{content:"\f2ce"}.fa-poll:before{content:"\f681"}.fa-poll-h:before{content:"\f682"}.fa-poo:befor...