[Haskell-cafe] Set (Set a) like container - but more efficient?

[Marc Weber]

Excerpts from Johannes Waldmann's message of Mon Sep 01 11:13:56 +0000 2014:
> Do you perhaps want a disjoint-set representation?
> http://stackoverflow.com/questions/15691696/equivalence-classes-and-union-find-in-a-functional-language

It turned out that the tree was that small that there was no need to
optimize the representation - thus using Set (Set a) was just good
enough.

Marc Weber