import Bag ( Bag, isEmptyBag, mapBag, emptyBag, bagToList )
import CoreLint ( showPass, endPass )
import CoreFVs ( ruleRhsFreeVars )
import Bag ( Bag, isEmptyBag, mapBag, emptyBag, bagToList )
import CoreLint ( showPass, endPass )
import CoreFVs ( ruleRhsFreeVars )