Rene2008 (2) [Avatar] Offline
On page 142 of rev 0 of the book, the book states:

“the Distinct operator uses the elements implementation of the IEquatable<T>.Equals method if the element implement the IEquatalbe<T> interface. It uses their implementation of Objec.Equals method otherwise.

I think the correct thing to say would be:

“the Distinct operator uses the default equality comparer, Default, to compare values if an IEqualityComparer is not provided”.

The problem with the book is that is says that Distinct uses IEquatable but after looking at the code using Reflector I was not able to verify that. According to me, the Distinct method uses IEqualityComparer via the “Set<TElement>” internal class. This “Set<Telement>” class appears to be a utility class used by the Distinct enumerator.

I may be wrong about this but I figure there is nothing to lose if I bring it up just to confirm.

Rene2008 (2) [Avatar] Offline
Re: Distinct
Never mind, I just looked at the:

private static EqualityComparer<T> CreateComparer()

of the "EqualityComparer<T>"

Sorry about that. I tried to delete the message but I couldn’t find the option to do that!!