Proposal #2629: Data.List: Replace nub; add nubOrd, nubInt, nubWith

Bart Massey bart at
Tue Sep 30 11:55:58 EDT 2008

Johannes Waldmann <waldmann <at>> writes:
> >  The StopList class  [...]
> BTW, that is a horrible name for what is simply a *set*
> (look at the methods you wrote: empty, insert, member).

I originally called the typeclass Set, but it isn't, so I changed it.  It omits
some Set functionality.  One couldn't write an implementation of union or
intersect with it, because there's no way to enumerate its elements.

In any case, it's moot, because we're ditching StopLists. :-)

> The design problem here is that you don't want to use Data.Set
> because currently it is an implementation, not an interface.

If by that you mean that it would be nice if Set was a typeclass, and there was
a [] implementation as well as the current OrdSet implementation, I tend to
agree.  C'est la vie.

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