prop_foldl1 xs n f = (n > 0 && not (null xs)) ==>
 runner1 (enumSpecial xs n (Iter.foldl1 f)) == P.foldl1 f xs
  where types = (xs :: [Int])
prop_foldl1 xs n f = (n > 0 && not (null xs)) ==>
 runner1 (enumSpecial xs n (Iter.foldl1 f)) == P.foldl1 f xs
  where types = (xs :: [Int])
prop_foldl1 xs n f = (n > 0 && not (null xs)) ==>
 runner1 (enumSpecial xs n (Iter.foldl1 f)) == P.foldl1 f xs
  where types = (xs :: [Int])