updateIl :: Instance.List           -- ^ The original instance list
         -> Maybe Node.AllocElement -- ^ The result of the allocation attempt
         -> Instance.List           -- ^ The updated instance list
updateIl il Nothing = il
updateIl :: Instance.List           -- ^ The original instance list
         -> Maybe Node.AllocElement -- ^ The result of the allocation attempt
         -> Instance.List
updateIl il Nothing = il
updateIl il Nothing = il