Proposal: Add Data.List.sortNub and sortNubBy

Neil Mitchell ndmitchell at
Tue Mar 13 05:38:14 EDT 2007


> sortNub = Data.Set.toList . Data.Set.fromList

This implementation seems to perform better on at least one particular
usage case. I'll take a closer look and see if this is always the

Are we going to have dependency problems by making Data.List depend on
Data.Set? My guess is yes, but I'm not sure.

> > I personally have defined this function at least 25 times, I suspect
> > others have to.
> Maybe you should have switched from lists to sets anyway.

I use Set's where appropriate, I use List's where appropriate. Just
because I'm using a list which I want nub'ing doesn't mean it is a
set. Set's also don't allow things like pattern matching, and don't
have the same range of functions over them, so lists are sometimes
easier for certain tasks.



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