How do I use toList with Oset in Haskell

Question

I have an algorithm which would benefit from the use of an Ordered Set (Oset) in Haskell. When I have such a Set I would like to convert it to a list where the order in the list is the insertion order in the set. The documentation for Data.Set.Ordered http://hackage.haskell.org/package/ordered-containers-0.2.2/docs/Data-Set-Ordered.html#t:OSet points me to Data.Foldable http://hackage.haskell.org/package/base-4.12.0.0/docs/Data-Foldable.html#v:toList to get what I require. But I don't seem to know enough Haskell to see how this helps. Can anyone give me an example of how to use an Ordered Set such that it implements .toList?

Answer 1

Data.Foldable.toList帮助，因为它可以在Foldable任何实例上工作，而Data.Set.Ordered.OSet是Foldable的实例。