BCL has introduced a group of Immutable Collections
I am wondering what's the difference between ImmutableSortedSet and the native FSharp Set? It seems that the performance signatures of both are similar. Also I saw somewhere that SortedSet is implemented as a Red Black Tree, so I guess ImmutableSortedSet does the same.
What is the internal implementation of fsharp map? Is is Red Black Tree as claimed here or AVL tree as found out here?
In addition, why MSDN documents don't state clear what the actual data structure is for the library collection? I know these are implementation details and are about to change. My point is that if they don't want to bind the library data type to a certain type of well known data structure, they should at least offer a summery of all the methods performance signatures in terms of complexity?