ruleLhsFreeIds :: CoreRule -> VarSet
-- ^ This finds all locally-defined free Ids on the left hand side of a rule
-- and returns them as a non-deterministic set
ruleLhsFreeIds = fvVarSet . ruleLhsFVIds
ruleLhsFreeIds :: CoreRule -> VarSet
ruleLhsFreeIds = fvVarSet . ruleLhsFVIds
ruleLhsFreeIds = fvVarSet . ruleLhsFVIds