nub package:infinite-list

Remove duplicate from a list, keeping only the first occurrence of each element. Because of a very weak constraint on a, this operation takes O(n²) time. Consider using nubOrd instead.
Overloaded version of nub. Consider using nubOrdBy instead.
Same as nub, but asymptotically faster, taking only O(n log n) time.
Overloaded version of nubOrd.