Data.IntSet.Optics

IntSet isn't Foldable, but this Fold can be used to access the members of an IntSet.

>>> sumOf members $ setOf folded [1,2,3,4]10

This Setter can be used to change the type of a IntSet by mapping the elements to new values.

Sadly, you can't create a valid Traversal for an IntSet, but you can manipulate it by reading using folded and reindexing it via setmapped.

>>> over setmapped (+1) (IntSet.fromList [1,2,3,4])fromList [2,3,4,5]

Construct an IntSet from a fold.

>>> setOf folded [1,2,3,4]fromList [1,2,3,4]

>>> setOf (folded % _2) [("hello",1),("world",2),("!!!",3)]fromList [1,2,3]