public static Func <DateTime, Boolean> ToLogic(this DateAnd dateAnd) => dateAnd.Terms.Select(c => c.ToLogic()).ToArray().ToAnd();
private static Unit WriteDateAnd(JsonTextWriter writer, DateAnd dateAnd) => nameof(DateAnd.Terms).WriteProperty(dateAnd.Terms.WriteArray((w, t) => t.WriteObject(WriteDateTerm)(w)))(writer);