about class Ref<T> { public T Value; }

[vanasis]

what is usage of "class Ref { public T Value; }"

[dadhi]

@vanasis The Ref is the helper abstraction to allow optimistic-concurrency Swap operation on the Value.
I am using it internally in DryIoc in concatenation with the immutable collections like ImHashMap to enable thread-safe set of the new value of the map without locking (this is the whole purpose of the optimistic concurrency). You may look through the Ref.Swap or just a .Swap method usages in Container.cs for the examples.