Proposal: IntMap.differenceKeysSet for removing an IntSet of keys

[Felipe Almeida Lessa]

If we had something like

  fromIntSet :: IntSet -> IntMap ()

then at least we could have a RULE to convert "difference m
(fromIntSet s)" to "differenceIntSet m s".  Then we could just hide
differenceIntSet and the name wouldn't matter.  Perhaps this
"fromIntSet" function should be proposed as well?

Cheers,

-- 
Felipe.