14 Jul
2013
14 Jul
'13
7:45 a.m.
At Sun, 14 Jul 2013 07:31:05 -0400, Clark Gaebel wrote:
Similarly, I've always used:
import qualified Data.HashSet as S
nub :: Hashable a => [a] -> [a] nub = S.toList . S.fromList
And i can't think of any type which i can't write a Hashable instance, so this is extremely practical.
Well, the above is not stable while Niklas’ is. But I guess that’s not the point of your message :). I’ve always avoided “nub” too, and FWIW I’d like a constrained version too—maybe avoiding Data.Set so that it could live in Data.List. I think Ord would be much better than Hashable, since it is 1. in “base” 2. much more established and understood. Although if you find yourself using “nub” too much you’re probably doing something wrong... Francesco