On 06/03/2011 11:37 PM, Christopher Howard wrote:
> Weird request: For a certain application, the "nub" function from
> Data.List is exactly what I need... almost. Nub removes duplicates,
> keeping the /first/ occurrence of each element. However, I need a
> function that removes duplicates, keeping the /second/ occurrence of
> each element. There wouldn't happen to be a function already that does
> this, would there?
>
> I'm working with a custom type which is a member of Eq, but some of the
> data in the type is not used in the comparison. So it is important which
> of the two "duplicates" are actually saved.
>
I should qualify this: By "second" I mean "last". Of course, it is
possible for there to be more than one duplicate of any given element in
a list. E.g., if there are three identical elements in a list, I want
the third one, not the second one.