Status of nubOrd (Proposal #2629)

[Simon Marlow]

Bart Massey wrote:

> 2) Stick (non-StopList) nubWith in Data.List.  Stick nubOrd
>    in Data.Set, implemented using nubWith.
> 
>    Advantages: Provides a highly efficient, fully lazy
>    nubOrd.  Provides nubWith.  Reasonable implementation.
> 
>    Disadvantages:  Sticking nubOrd in Data.Set is weird.
> 
>    My score: 4/5

(2) seems reasonable to me, as long as we improve the documentation for nub 
to point out the quadratic complexity and direct users who want a faster 
version to Data.Set.nubOrd.

Cheers,
	Simon