nubInt is:exact

The nubInt function removes duplicate Int values from a list. In particular, it keeps only the first occurrence of each element. By using an IntSet internally, it attains better asymptotics than the standard nub function. See also nubIntOn, a more widely applicable generalization.

Strictness

nubInt is strict in the elements of the list.
More efficient versions of above when working with Ints that use IntSet.
Like nub but specialized to a stream of Int, for better performance. Pre-release