Internal System.Linq.Set vs public System.Collections.Generic.HashSet

Question

Check out this piece of code from Linq.Enumerable class:

static IEnumerable DistinctIterator(IEnumerable

        

Answer 1

The implementation of this Set<T> is far simpler than HashSet<T> as it is only needs to add and remove elements and check for existence for LINQ internal processes. It does not implement any interfaces or expose iterators etc.

So probably it is faster for the purpose LINQ uses it for.