C# (CSharp) ILens.Update примеры использования

Пример #1

 public static Whole Cons <T, Whole>(this T value, ILens <ImmutableList <T>, Whole> lens)
 => lens.Update(oldHole => value.Cons(oldHole));

Пример #2

 public static Whole Update <Hole, Whole>(this ILens <Hole, Whole> lens, Hole newHole)
 => lens.Update(oldHole => newHole);