code: public static <T extends Case3<A, B, C>, A, B, C> DecomposableMatchBuilder0<T> case3(
        Class<T> clazz, MatchesExact<A> a, MatchesExact<B> b, MatchesExact<C> c) {
      List<Matcher<Object>> matchers =
          Lists.of(ArgumentMatchers.eq(a.t), ArgumentMatchers.eq(b.t), ArgumentMatchers.eq(c.t));
      return new DecomposableMatchBuilder0<T>(matchers, new Case3FieldExtractor<>(clazz));
    }
docs: Matches a case class of three elements.