/// <summary>
 /// Project the Either into an ImmutableArray R
 /// </summary>
 /// <typeparam name="L">Left</typeparam>
 /// <typeparam name="R">Right</typeparam>
 /// <param name="either">Either to project</param>
 /// <returns>If the Either is in a Right state, a ImmutableArray of R with one item.  A zero length ImmutableArray of R otherwise</returns>
 public static R[] rightToArray <L, R>(EitherUnsafe <L, R> either) =>
 either.RightToArray();